diff --git a/html/arabic/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/arabic/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..eaa230328 --- /dev/null +++ b/html/arabic/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: إنشاء PDF من Markdown في Java باستخدام Aspose.HTML – دليل سريع خطوة بخطوة + لتحويل markdown إلى PDF، حفظ markdown كملف PDF، وتعلم أساسيات تحويل markdown إلى + PDF في Java. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: ar +og_description: إنشاء ملف PDF من Markdown في Java باستخدام Aspose.HTML. تعلّم كيفية + تحويل Markdown إلى PDF، حفظ Markdown كملف PDF، والتعامل مع الحالات الخاصة الشائعة + في دليل مختصر. +og_title: إنشاء PDF من Markdown في Java – سطر واحد سريع +tags: +- Java +- PDF +- Markdown +title: إنشاء PDF من Markdown في Java – دليل سطر واحد بسيط +url: /ar/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# إنشاء PDF من Markdown في Java – دليل سطر واحد بسيط + +هل تساءلت يومًا كيف **تنشئ PDF من Markdown** دون الحاجة إلى التعامل مع عشرات المكتبات؟ لست وحدك. العديد من المطورين يحتاجون إلى تحويل ملاحظاتهم بصيغة `.md` إلى ملفات PDF مصقولة للتقارير أو الوثائق أو الكتب الإلكترونية، ويرغبون في حل يعمل بسطر واحد من كود Java. + +في هذا الدرس سنستعرض بالضبط ذلك: استخدام مكتبة Aspose.HTML for Java **لتحويل markdown إلى pdf** و**لحفظ markdown كـ pdf** بطريقة نظيفة وقابلة للصيانة. سنتطرق أيضًا إلى موضوع **java markdown to pdf** بشكل أوسع لتفهم السبب وراء كل خطوة، وليس فقط الطريقة. + +> **ما ستحصل عليه** +> برنامج Java كامل، قابل للتنفيذ، يقرأ `input.md`، يكتب `output.pdf`، ويطبع رسالة نجاح ودية. بالإضافة إلى معرفة كيفية تعديل التحويل، التعامل مع الملفات المفقودة، ودمج الكود في مشاريع أكبر. + +## المتطلبات المسبقة – ما تحتاجه قبل البدء + +- **Java Development Kit (JDK) 11 أو أحدث** – يستخدم الكود `java.nio.file.Paths` المتاح منذ JDK 7، لكن JDK 11 هو الإصدار LTS الحالي ويضمن التوافق مع Aspose.HTML. +- **Aspose.HTML for Java** (الإصدار 23.9 أو أحدث). يمكنك الحصول عليه من Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **ملف Markdown** (`input.md`) موجود في مكان يمكنك الإشارة إليه. إذا لم يكن لديك ملف، أنشئ ملفًا صغيرًا يحتوي على بعض العناوين وقائمة – المكتبة ستتعامل مع أي Markdown صالح. +- **IDE أو مجرد `javac`/`java`** – سنبقي الكود Java نقيًا، دون الحاجة إلى Spring أو أطر أخرى. + +> **نصيحة محترف:** إذا كنت تستخدم Maven، أضف الاعتماد إلى `pom.xml` وشغّل `mvn clean install`. إذا كنت تفضّل Gradle، فالمكافئ هو `implementation 'com.aspose:aspose-html:23.9'`. + +## نظرة عامة – إنشاء PDF من Markdown بلمسة واحدة + +فيما يلي البرنامج الكامل الذي سنبنيه. لاحظ **النداء الواحد** إلى `Converter.convert(...)`؛ هذا هو جوهر عملية **إنشاء pdf من markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +تشغيل هذه الفئة سيقرأ `input.md`، يولّد `output.pdf`، ويطبع سطر التأكيد. هذا كل شيء—**سير عمل `create pdf from markdown` بالكامل في أقل من 30 سطرًا** (بما في ذلك التعليقات). + +## شرح خطوة بخطوة + +### 1️⃣ تعريف ملفات المصدر والوجهة + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **لماذا نستخدم `Paths.get`**: يبني مسارًا مستقلاً عن نظام التشغيل، ويتعامل تلقائيًا مع الفواصل الخلفية في Windows والشرطية في Unix. +- **حالة حافة**: إذا لم يكن ملف Markdown موجودًا، فإن `Converter.convert` يرمي `FileNotFoundException`. يمكنك التحقق مسبقًا باستخدام `Files.exists(Paths.get(markdownPath))` وإظهار رسالة خطأ ودية. + +### 2️⃣ إعداد خيارات حفظ PDF (تعديلات اختيارية) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **السلوك الافتراضي**: سيستخدم PDF حجم صفحة A4، وهوامش افتراضية، ويضمّن الخطوط تلقائيًا. +- **التخصيص**: هل تريد تخطيطًا أفقيًا؟ استخدم `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **نصيحة أداء**: للملفات الكبيرة، يمكنك تمكين `pdfOptions.setEmbedStandardFonts(false)` لتقليل حجم الملف على حساب اختلافات محتملة في العرض. + +### 3️⃣ تنفيذ التحويل – قلب “Convert Markdown to PDF” + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **ما يحدث خلف الكواليس**: تقوم Aspose.HTML بتحليل Markdown إلى DOM HTML داخلي، ثم تُحوّل هذا الـ DOM إلى PDF باستخدام محرك التخطيط عالي الدقة. +- **لماذا هذا هو النهج الموصى به**: مقارنةً بأنابيب HTML‑to‑PDF اليدوية (مثل wkhtmltopdf)، تتعامل Aspose مع CSS والجداول والصور والـ Unicode مباشرة، مما يجعل سؤال **how to convert markdown** بسيطًا. + +### 4️⃣ رسالة التأكيد + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +لمسة UX صغيرة—مفيدة خصوصًا عندما يُشغَّل البرنامج كجزء من مهمة دفعة أكبر. + +## التعامل مع المشكلات الشائعة + +| المشكلة | العرض | الحل | +|-------|---------|-----| +| **ملف Markdown مفقود** | `FileNotFoundException` | تحقق من المسار مسبقًا: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **صور غير مدعومة** | تظهر الصور كعناصر نائبة مكسورة في PDF | تأكد من أن الصور مُشار إليها بمسارات مطلقة أو دمجها كـ Base64 في Markdown. | +| **المستندات الكبيرة تسبب OOM** | `OutOfMemoryError` | زد حجم heap للـ JVM (`-Xmx2g`) أو قسّم الـ Markdown إلى أقسام وحوّل كل قسم على حدة، ثم دمج ملفات PDF (توفر Aspose دمج `PdfFile`). | +| **خطوط خاصة مفقودة** | النص يُعرض بخط بديل | ثبّت الخطوط المطلوبة على الجهاز أو ضمّنها يدويًا عبر `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## توسيع السطر الواحد: سيناريوهات واقعية + +### أ. تحويل دفعة من ملفات متعددة + +إذا احتجت إلى **حفظ markdown كـ pdf** لمجلد كامل، ضع التحويل داخل حلقة: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### ب. إضافة رأس/تذييل مخصص + +لنفترض أنك تريد عرض شعار ورقم صفحة في كل صفحة. استخدم `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +الآن كل PDF مُولَّد يحمل العلامة التجارية التي تحتاجها—مثالي للوثائق المؤسسية. + +### ج. دمجها في خدمة Spring Boot + +اعرض التحويل كواجهة REST: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +بهذا تصبح قدرة **java markdown to pdf** متاحة لأي عميل—محمول، ويب، أو سطح مكتب. + +## النتيجة المتوقعة + +بعد تشغيل `MdToPdfOneLiner` الأصلي، يجب أن ترى ملفًا جديدًا `output.pdf` في المجلد الذي حددته. عند فتحه ستظهر محتويات Markdown مُعالجة بعناوين صحيحة، قوائم، كتل شفرة، وأي صور أدرجتها. الـ PDF قابل للبحث، ويمكن نسخ النص منه—على عكس ملفات PDF التي تحتوي على صور فقط. + +## الأسئلة المتكررة + +**س: هل يعمل هذا على macOS/Linux كما على Windows؟** +ج: بالتأكيد. نداء `Paths.get` يختزل الفواصل الخاصة بأنظمة التشغيل، وAspose.HTML متعدد المنصات. + +**س: هل يمكنني تحويل لغات توصيف أخرى (مثل AsciiDoc) باستخدام نفس الـ API؟** +ج: طريقة `Converter.convert` تدعم HTML، CSS، وMarkdown مباشرة. بالنسبة لـ AsciiDoc تحتاج أولًا إلى تحويله إلى HTML (مثلاً باستخدام AsciidoctorJ) ثم تمرير الـ HTML إلى Aspose. + +**س: هل هناك نسخة مجانية من Aspose.HTML؟** +ج: تقدم Aspose رخصة تقييم لمدة 30 يومًا مع جميع الوظائف. للاستخدام الإنتاجي، يلزم الحصول على رخصة تجارية. + +## الخاتمة – لقد أتقنت إنشاء PDF من Markdown في Java + +انتقلنا معك من سؤال المشكلة—*كيف أنشئ PDF من markdown؟*—إلى حل مختصر قابل للتنفيذ، ثم إلى توسيعات واقعية مثل المعالجة الدفعة وخدمات الويب. باستخدام طريقة `Converter.convert` من Aspose.HTML، يمكنك **تحويل markdown إلى pdf** ببضع أسطر من الكود، مع الحفاظ على القدرة على تخصيص حجم الصفحة، الرؤوس، التذييلات، وإعدادات الأداء. + +الخطوات التالية؟ جرّب استبدال `PdfSaveOptions` الافتراضية بملف CSS مخصص، جرب تضمين الخطوط، أو اربط التحويل بخط أنابيب CI بحيث يُنتج كل README ملف PDF تلقائيًا. السماء هي الحد عندما تكون لديك أساسيات **java markdown to pdf** تحت سيطرتك. + +برمجة سعيدة، ولتظهر ملفات PDF دائمًا كما تخيلتها! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/arabic/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/arabic/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..53051b362 --- /dev/null +++ b/html/arabic/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: كيفية ضبط DPI عند تحويل عنوان URL إلى PNG. تعلم كيفية تحويل HTML إلى + PNG، ضبط حجم نافذة العرض، وحفظ HTML كملف PNG باستخدام Aspose.HTML في Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: ar +og_description: كيفية ضبط DPI عند تحويل عنوان URL إلى PNG. دليل خطوة بخطوة لتصوير + HTML إلى PNG، التحكم في حجم نافذة العرض، وحفظ HTML كملف PNG باستخدام Aspose.HTML. +og_title: كيفية ضبط DPI – تحويل HTML إلى PNG باستخدام AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: كيفية تعيين DPI – تحويل HTML إلى PNG باستخدام AsposeHTML +url: /ar/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# كيفية ضبط DPI – تحويل HTML إلى PNG باستخدام AsposeHTML + +هل تساءلت يومًا **كيف يتم ضبط DPI** لصورة تشبه لقطة شاشة تم إنشاؤها من صفحة ويب؟ ربما تحتاج إلى صورة PNG بدقة 300 DPI للطباعة، أو صورة مصغرة منخفضة الدقة لتطبيق هاتف محمول. في كلتا الحالتين، الحيلة هي إخبار محرك العرض ما هو DPI المنطقي الذي تريده، ثم تركه يقوم بالعمل الشاق. + +في هذا البرنامج التعليمي سنأخذ عنوان URL حي، نحوله إلى ملف PNG، **نضبط حجم نافذة العرض**، نعدّل DPI، وأخيرًا **نحفظ HTML كـ PNG**—كل ذلك باستخدام Aspose.HTML for Java. لا متصفحات خارجية، لا أدوات سطر أوامر فوضوية—فقط كود Java نظيف يمكنك وضعه في أي مشروع Maven أو Gradle. + +> **نصيحة احترافية:** إذا كنت تحتاج فقط إلى صورة مصغرة سريعة، يمكنك إبقاء DPI عند 96 DPI (الإعداد الافتراضي لمعظم الشاشات). للأصول الجاهزة للطباعة، ارتقِ به إلى 300 DPI أو أكثر. + +![مثال على كيفية ضبط DPI](https://example.com/images/how-to-set-dpi.png "مثال على كيفية ضبط DPI") + +## ما ستحتاجه + +- **Java 17** (أو أي JDK حديث). +- **Aspose.HTML for Java** 24.10 أو أحدث. يمكنك الحصول عليه من Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- اتصال بالإنترنت لجلب الصفحة المستهدفة (المثال يستخدم `https://example.com/sample.html`). +- إذن كتابة إلى مجلد الإخراج. + +هذا كل شيء—لا Selenium، لا Chrome بدون رأس. Aspose.HTML يقوم بالعرض داخل العملية، مما يعني أنك تبقى داخل JVM وتتجنب عبء تشغيل المتصفح. + +## الخطوة 1 – تحميل مستند HTML من عنوان URL + +أولاً ننشئ كائن `HTMLDocument` يشير إلى الصفحة التي نريد التقاطها. يقوم المُنشئ تلقائيًا بتحميل HTML، تحليله، وتحضير DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*لماذا هذا مهم:* بتحميل المستند مباشرةً، تتجاوز الحاجة إلى عميل HTTP منفصل. Aspose.HTML يحترم عمليات إعادة التوجيه، ملفات تعريف الارتباط، وحتى المصادقة الأساسية إذا قمت بدمج بيانات الاعتماد في عنوان URL. + +## الخطوة 2 – بناء Sandbox مع DPI وحجم نافذة العرض المطلوبين + +**sandbox** هو طريقة Aspose.HTML لمحاكاة بيئة المتصفح هنا نخبره بأنه يتصرف كأنه شاشة بحجم 1280 × 720، والأهم أننا نضبط **Device DPI**. تغيير DPI يغيّر كثافة البكسل للصورة المرسومة دون تعديل الحجم المنطقي. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*لماذا قد تحتاج إلى تعديل هذه القيم:* +- **Viewport size** يتحكم في سلوك استعلامات وسائط CSS (`@media (max-width: …)`). +- **Device DPI** يؤثر على الحجم الفعلي للصورة عند الطباعة. صورة بدقة 96 DPI تبدو جيدة على الشاشات؛ صورة بدقة 300 DPI تحتفظ بوضوحها على الورق. + +إذا كنت تحتاج إلى صورة مصغرة مربعة، ببساطة غير `setViewportSize(500, 500)` وأبقِ DPI منخفضًا. + +## الخطوة 3 – اختيار PNG كصيغة الإخراج + +Aspose.HTML يدعم عدة صيغ نقطية (PNG, JPEG, BMP, GIF). PNG غير مضغوط، مما يجعله مثاليًا للقطات الشاشة التي تريد فيها الحفاظ على كل بكسل. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +يمكنك أيضًا تعديل مستوى الضغط (`pngOptions.setCompressionLevel(9)`) إذا كنت قلقًا بشأن حجم الملف. + +## الخطوة 4 – العرض وحفظ الصورة + +الآن نخبر المستند بـ **حفظ** نفسه كصورة. طريقة `save` تأخذ مسار الملف والخيارات التي تم تكوينها مسبقًا. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +عند انتهاء البرنامج، ستجد ملف PNG في `YOUR_DIRECTORY/sandboxed.png`. افتحه—إذا ضبطت DPI على 300، ستعكس بيانات تعريف الصورة ذلك، رغم أن أبعاد البكسل تظل 1280 × 720. + +## الخطوة 5 – التحقق من DPI (اختياري لكن مفيد) + +إذا أردت التأكد مرة أخرى من تطبيق DPI فعليًا، يمكنك قراءة بيانات تعريف PNG باستخدام مكتبة خفيفة مثل **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +يجب أن ترى `300` (أو أي قيمة ضبطتها) مطبوعة في وحدة التحكم. هذه الخطوة ليست ضرورية للعرض، لكنها فحص سريع للمنطق، خاصةً عندما تُنشئ أصولًا لسير عمل الطباعة. + +## أسئلة شائعة وحالات خاصة + +### “ماذا لو استخدمت الصفحة JavaScript لتحميل المحتوى؟” + +Aspose.HTML ينفذ **مجموعة محدودة** من JavaScript. بالنسبة لمعظم المواقع الثابتة يعمل مباشرةً. إذا كانت الصفحة تعتمد بشكل كبير على أطر عمل من جانب العميل (React, Angular, Vue)، قد تحتاج إلى عرض مسبق للصفحة أو استخدام متصفح بدون رأس بدلاً من ذلك. ومع ذلك، ضبط DPI يعمل بنفس الطريقة بمجرد أن يصبح DOM جاهزًا. + +### “هل يمكنني عرض PDF بدلاً من PNG؟” + +بالتأكيد. استبدل `ImageSaveOptions` بـ `PdfSaveOptions` وغير امتداد الإخراج إلى `.pdf`. لا يزال ضبط DPI يؤثر على المظهر النقطي لأي صور مدمجة. + +### “ماذا عن لقطات الشاشة عالية الدقة لشاشات Retina؟” + +ما عليك سوى مضاعفة أبعاد نافذة العرض مع إبقاء DPI عند 96 DPI، أو إبقاء نافذة العرض ومضاعفة DPI إلى 192. سيتضمن PNG الناتج ضعف عدد البكسلات، مما يمنحك وضوح Retina. + +### “هل أحتاج إلى تنظيف الموارد؟” + +`HTMLDocument` ينفذ `AutoCloseable`. في تطبيق إنتاجي، احيطه بكتلة try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +هذا يضمن تحرير الموارد الأصلية على الفور. + +## مثال كامل يعمل (جاهز للنسخ واللصق) + +فيما يلي البرنامج الكامل الجاهز للتنفيذ. استبدل `YOUR_DIRECTORY` بمجلد فعلي على جهازك. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +شغّل الفئة، وستحصل على PNG يحترم إعداد **كيفية ضبط DPI** الذي حددته. + +## الخلاصة + +لقد استعرضنا **كيفية ضبط DPI** عند **تحويل HTML إلى PNG**، وتناولنا خطوة **ضبط حجم نافذة العرض**، وأظهرنا لك كيفية **حفظ HTML كـ PNG** باستخدام Aspose.HTML for Java. النقاط الرئيسية هي: + +- استخدم **sandbox** للتحكم في DPI وحجم نافذة العرض. +- اختر **ImageSaveOptions** المناسبة للإخراج غير المضغوط. +- تحقق من بيانات تعريف DPI إذا كنت بحاجة لضمان جودة الطباعة. + +من هنا يمكنك تجربة قيم DPI مختلفة، أو نوافذ عرض أكبر، أو حتى معالجة مجموعة من عناوين URL دفعة واحدة. هل تريد تحويل موقع كامل إلى صور PNG مصغرة؟ فقط كرّر حلقة عبر مصفوفة من عناوين URL وأعد استخدام نفس تكوين sandbox. + +نتمنى لك عرضًا موفقًا، ولتكن لقطات الشاشة دائمًا ذات دقة بكسلية مثالية! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/arabic/java/css-html-form-editing/_index.md b/html/arabic/java/css-html-form-editing/_index.md index 880540046..257f91a97 100644 --- a/html/arabic/java/css-html-form-editing/_index.md +++ b/html/arabic/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ url: /ar/java/css-html-form-editing/ تعرف على كيفية استخدام Aspose.HTML for Java لتطبيق تقنيات CSS المتقدمة، بما في ذلك هوامش الصفحات المخصصة والمحتوى الديناميكي. برنامج تعليمي عملي مفصل للمطورين. ### [تحرير نماذج HTML وإرسالها باستخدام Aspose.HTML لـ Java](./html-form-editing/) تعرف على كيفية تحرير نماذج HTML وإرسالها برمجيًا باستخدام Aspose.HTML لـ Java في هذا الدليل الشامل خطوة بخطوة. +### [كيفية الحصول على النمط في Java – تحميل HTML واستخدام محدد الاستعلام](./how-to-get-style-in-java-load-html-query-selector/) +تعلم كيفية تحميل مستند HTML واستخراج الأنماط باستخدام محددات الاستعلام في Aspose.HTML for Java. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/arabic/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/arabic/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..fd88f3f5a --- /dev/null +++ b/html/arabic/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: كيفية الحصول على النمط في Java – تعلم كيفية تحميل مستند HTML، واستخدام + مثال محدد الاستعلام، وقراءة خاصية background‑color باستخدام Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: ar +og_description: كيفية الحصول على النمط في جافا – دليل خطوة بخطوة لتحميل مستند HTML، + تشغيل مثال على محدد الاستعلام، وجلب خاصية لون الخلفية. +og_title: كيفية الحصول على النمط في جافا – تحميل HTML ومحدد الاستعلام +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: كيفية الحصول على النمط في جافا – تحميل HTML ومحدد الاستعلام +url: /ar/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# كيفية الحصول على النمط في Java – تحميل HTML واستخدام query selector + +هل تساءلت يوماً **كيف تحصل على النمط** لعنصر عندما تقوم بتحليل HTML باستخدام Java؟ ربما تقوم بإنشاء أداة استخراج، أو أداة اختبار، أو تحتاج فقط إلى التحقق من الإشارات البصرية في صفحة مُولَّدة. الخبر السار هو أن Aspose.HTML يجعل ذلك سهلًا للغاية. في هذا الدرس سنستعرض تحميل مستند HTML، واستخدام **مثال على query selector**، وأخيرًا قراءة **خاصية background-color** لعنصر `
`. لا سحر، فقط كود Java واضح يمكنك نسخه‑ولصقه وتشغيله. + +## ما ستحتاجه + +قبل أن نبدأ، تأكد من وجود ما يلي: + +* **Java 17** (أو أي JDK حديث) – الواجهة البرمجية تعمل مع Java 8+ لكن الإصدارات الأحدث تعطي أداءً أفضل. +* مكتبة **Aspose.HTML for Java** – يمكنك الحصول عليها من Maven Central (`com.aspose:aspose-html:23.10` في وقت كتابة هذا الدرس). +* ملف HTML صغير (`input.html`) يحتوي على عنصر `
` واحد على الأقل مع خاصية CSS للون الخلفية مُحددة إما داخل العنصر أو عبر ورقة أنماط. + +هذا كل شيء. لا أطر إضافية، لا متصفحات ثقيلة، فقط Java عادية وAspose.HTML. + +## الخطوة 1: تحميل مستند HTML + +أول شيء عليك القيام به هو **load html document** في الذاكرة. فئة `HTMLDocument` في Aspose.HTML تُجرد لك التعامل مع نظام الملفات وتُعطيك DOM يمكنك الاستعلام عنه. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **لماذا هذا مهم:** تحميل المستند يُنشئ شجرة DOM مُحلَّلة، وهي الأساس لأي تقييم لاحق للـ CSS أو JavaScript. إذا تعذر العثور على الملف، تُطلق Aspose استثناءً وصفيًا `FileNotFoundException`، لذا تحقق من المسار مرة أخرى. + +### نصيحة احترافية +إذا كنت تجلب HTML من عنوان URL بدلاً من ملف، ما عليك سوى تمرير سلسلة URL إلى المُنشئ – Aspose تتولى طلب HTTP لك. + +## الخطوة 2: استخدام مثال Query Selector + +الآن بعد أن أصبح المستند في الذاكرة، دعنا **query selector example** للحصول على أول عنصر `
`. طريقة `querySelector` تعكس صsyntax محددات CSS التي تعرفها من المتصفح. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **لماذا هذا مهم:** `querySelector` تُعيد أول عقدة مطابقة، وهو مثالي عندما تحتاج فقط إلى نمط عنصر واحد. إذا كنت تحتاج إلى عناصر متعددة، فإن `querySelectorAll` تُعيد `NodeList`. + +### حالة حافة +إذا لم يتطابق المحدد مع أي شيء، سيكون `divElement` يساوي `null`. احرص دائمًا على التحقق من ذلك قبل محاولة قراءة الأنماط: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## الخطوة 3: الحصول على النمط المحسوب + +مع العنصر في يدك، الخطوة التالية هي **parse html java** بما يكفي لحساب القيم النهائية للـ CSS. Aspose.HTML تقوم بالعمل الشاق: فهي تحل التسلسل الهرمي، والوراثة، وحتى أوراق الأنماط الخارجية. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **لماذا هذا مهم:** النمط المحسوب يعكس القيم الدقيقة التي سيطبقها المتصفح بعد معالجة جميع قواعد CSS. وهو أكثر موثوقية من قراءة السمة `style` الخام، التي قد تكون غير مكتملة. + +## الخطوة 4: استرجاع خاصية background‑color + +أخيرًا، نستخرج **background-color property** التي نهتم بها. طريقة `getPropertyValue` تُعيد القيمة كسلسلة نصية (مثال: `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **ما ستراه:** إذا كان `
` يحتوي على `background-color: #ff5733;` سواءً داخل العنصر أو عبر ورقة أنماط، سيطبع الطرفية شيءً مثل `Computed background‑color: rgb(255, 87, 51)`. + +### خطأ شائع +عندما لا تكون الخاصية معرفة، تُعيد `getPropertyValue` سلسلة فارغة. هذا إشارة إما للعودة إلى قيمة افتراضية أو فحص أنماط العنصر الأب. + +## مثال كامل يعمل + +نجمع كل ما سبق في برنامج كامل جاهز للتنفيذ: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**الناتج المتوقع (مثال):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +إذا لم يكن للـ `
` لون خلفية مُحدد، سيكون الناتج سطرًا فارغًا – هذه إشارة للبحث في الأنماط الموروثة. + +## نصائح، حيل، وأشياء يجب الانتباه إليها + +| الحالة | ما يجب فعله | +|-----------|------------| +| **عدة عناصر `
`** | استخدم `querySelectorAll("div")` وتكرّر على `NodeList`. | +| **ملفات CSS خارجية** | تأكد من أن ملف HTML يشير إليها بمسارات صحيحة؛ Aspose.HTML ستجلبها تلقائيًا. | +| **سمة `style` داخلية فقط** | `getComputedStyle` ما زالت تعمل – فهي تُدمج الأنماط الداخلية مع القيم الافتراضية. | +| **مخاوف الأداء** | حمّل المستند مرة واحدة، وأعد استخدام كائن `HTMLDocument` إذا كنت تحتاج إلى استعلام عدة عناصر. | +| **التشغيل على Android** | Aspose.HTML for Java يدعم Android، لكن سيتوجب عليك تضمين الـ AAR الخاص بـ Android. | + +## مواضيع ذات صلة قد ترغب في استكشافها + +* **تحليل HTML باستخدام Jsoup مقابل Aspose.HTML** – متى تختار أحدهما على الآخر. +* **تصدير الأنماط المحسوبة إلى JSON** – مفيد للواجهات الأمامية المدفوعة بـ API. +* **أتمتة إنشاء لقطات الشاشة** – دمج الأنماط المحسوبة مع Aspose.PDF لاختبار الانحدار البصري. + +--- + +### الخلاصة + +أنت الآن تعرف **كيفية الحصول على النمط** لأي عنصر عندما **load html document** باستخدام Aspose.HTML، وتشغيل **مثال query selector**، واستخراج **خاصية background-color**. الكود مستقل، يعمل على أي JDK حديث، ويتعامل بأناقة مع العناصر المفقودة أو الأنماط غير المعرفة. من هنا يمكنك توسيع النهج للحصول على أحجام الخطوط، الهوامش، أو حتى القيم المحسوبة بعد تنفيذ JavaScript (Aspose.HTML يدعم أيضًا تقييم السكريبتات). + +جرّبه، عدّل المحدد، واكتشف ما هي الكنوز الأخرى في CSS. Happy coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/chinese/java/conversion-html-to-other-formats/_index.md b/html/chinese/java/conversion-html-to-other-formats/_index.md index 748999606..c7fc6919d 100644 --- a/html/chinese/java/conversion-html-to-other-formats/_index.md +++ b/html/chinese/java/conversion-html-to-other-formats/_index.md @@ -95,6 +95,8 @@ Aspose.HTML for Java 简化了 HTML 转 PDF 的工作流。请参阅专门的教 使用 Aspose.HTML 在 Java 中将 SVG 转换为 PDF。提供高质量文档转换的无缝解决方案。 ### [将 SVG 转换为 XPS](./convert-svg-to-xps/) 了解如何使用 Aspose.HTML for Java 将 SVG 转换为 XPS。提供简单、分步的无缝转换指南。 +### [在 Java 中从 Markdown 创建 PDF – 简单单行指南](./create-pdf-from-markdown-in-java-simple-one-liner-guide/) +使用 Aspose.HTML for Java 的一行代码将 Markdown 文档直接转换为 PDF,快速高效。 ## 常见问题 @@ -124,4 +126,4 @@ Aspose.HTML for Java 简化了 HTML 转 PDF 的工作流。请参阅专门的教 {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/chinese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/chinese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..29ef99a73 --- /dev/null +++ b/html/chinese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Create PDF from Markdown in Java using Aspose.HTML – a quick step‑by‑step + tutorial to convert markdown to pdf, save markdown as pdf, and learn java markdown + to pdf basics. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: zh +og_description: Create PDF from Markdown in Java with Aspose.HTML. Learn how to convert + markdown to pdf, save markdown as pdf, and handle common edge cases in a concise + tutorial. +og_title: Create PDF from Markdown in Java – Quick One‑Liner +tags: +- Java +- PDF +- Markdown +title: Create PDF from Markdown in Java – Simple One‑Liner Guide +url: /zh/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# 在 Java 中从 Markdown 创建 PDF – 简单单行指南 + +是否曾经想过如何 **create PDF from Markdown** 而不需要与数十个库斗争?你并不孤单。许多开发者需要将他们的 `.md` 笔记转换为精美的 PDF,用于报告、文档或电子书,并且他们希望有一个只需一行 Java 代码即可实现的解决方案。 + +在本教程中,我们将逐步演示:使用 Aspose.HTML for Java 库来 **convert markdown to pdf** 和 **save markdown as pdf**,以简洁、可维护的方式。我们还会涉及更广泛的 **java markdown to pdf** 主题,让你了解每一步背后的原因,而不仅仅是操作方法。 + +> **你将收获** +> 一个完整的、可运行的 Java 程序,读取 `input.md`,生成 `output.pdf`,并打印友好的成功信息。此外,你还将了解如何微调转换、处理缺失文件以及将代码集成到更大的项目中。 + +## 前置条件 – 开始之前需要准备的东西 + +- **Java Development Kit (JDK) 11 或更高** – 代码使用 `java.nio.file.Paths`,自 JDK 7 起可用,但 JDK 11 是当前的 LTS,并确保与 Aspose.HTML 的兼容性。 +- **Aspose.HTML for Java**(版本 23.9 或更高)。你可以从 Maven Central 获取: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **Markdown 文件**(`input.md`),放在你可以引用的位置。如果没有,可以创建一个包含几个标题和列表的小文件——库能够处理任何有效的 Markdown。 +- **IDE 或纯 `javac`/`java`** – 我们将保持代码纯 Java,不需要 Spring 或其他框架。 + +> **专业提示:** 如果使用 Maven,请将依赖添加到 `pom.xml` 并运行 `mvn clean install`。如果更喜欢 Gradle,则等价写法是 `implementation 'com.aspose:aspose-html:23.9'`。 + +## 概览 – 一次性从 Markdown 创建 PDF + +下面是我们将构建的完整程序。请注意对 `Converter.convert(...)` 的 **单次调用**;这就是 **create pdf from markdown** 操作的核心。 + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +运行此类将读取 `input.md`,生成 `output.pdf`,并输出确认行。就这样——**整个 `create pdf from markdown` 工作流不到 30 行**(包括注释)。 + +## 步骤分解 + +### 1️⃣ 定义源文件和目标文件 + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **为什么使用 `Paths.get`**:它构建了与操作系统无关的路径,自动处理 Windows 的反斜杠和 Unix 的正斜杠。 +- **边缘情况**:如果 Markdown 文件不存在,`Converter.convert` 会抛出 `FileNotFoundException`。你可以使用 `Files.exists(Paths.get(markdownPath))` 进行预检查,并给出友好的错误提示。 + +### 2️⃣ 设置 PDF 保存选项(可选调整) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **默认行为**:PDF 将使用 A4 页面尺寸、默认边距,并自动嵌入字体。 +- **自定义**:想要横向布局?使用 `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`。 +- **性能提示**:对于大型 Markdown 文件,你可以启用 `pdfOptions.setEmbedStandardFonts(false)` 来减小文件大小,但可能会导致渲染差异。 + +### 3️⃣ 执行转换 – “Convert Markdown to PDF”的核心 + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **内部工作原理**:Aspose.HTML 将 Markdown 解析为内部的 HTML DOM,然后使用其高保真布局引擎将该 DOM 渲染为 PDF。 +- **为何推荐此方法**:相较于手写的 HTML‑to‑PDF 流程(例如使用 wkhtmltopdf),Aspose 开箱即支持 CSS、表格、图像和 Unicode,使 **how to convert markdown** 的问题变得微不足道。 + +### 4️⃣ 确认信息 + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +一个小小的用户体验细节——在程序作为更大批处理作业的一部分运行时尤其有用。 + +## 处理常见陷阱 + +| 问题 | 症状 | 解决方案 | +|-------|---------|-----| +| **缺少 Markdown 文件** | `FileNotFoundException` | 在此之前验证路径:`if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **不支持的图像** | PDF 中的图像显示为破损占位符 | 确保图像使用绝对路径引用,或在 Markdown 中以 Base64 嵌入它们。 | +| **大型文档导致 OOM** | `OutOfMemoryError` | 增加 JVM 堆内存 (`-Xmx2g`) 或将 Markdown 拆分为多个部分分别转换,然后合并 PDF(Aspose 提供 `PdfFile` 合并)。 | +| **缺少特殊字体** | 文本使用回退字体渲染 | 在主机上安装所需字体,或通过 `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` 手动嵌入它们。 | + +## 扩展单行代码:真实场景 + +### A. 批量转换多个文件 + +如果需要为整个文件夹 **save markdown as pdf**,可以将转换包装在循环中: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. 添加自定义页眉/页脚 + +假设你想让每页显示徽标和页码。使用 `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +现在每个生成的 PDF 都带有你需要的品牌标识——非常适合企业文档。 + +### C. 集成到 Spring Boot 服务中 + +将转换功能暴露为 REST 接口: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +现在 **java markdown to pdf** 能力对任何客户端——移动、网页或桌面——都可用。 + +## 预期输出 + +运行原始的 `MdToPdfOneLiner` 后,你应该在指定的文件夹中看到一个新文件 `output.pdf`。打开它会显示你的 Markdown 内容,带有正确的标题、列表、代码块以及任何你包含的图像。该 PDF 完全可搜索,文本可复制——不同于仅包含图像的 PDF。 + +## 常见问题 + +**Q: 这在 macOS/Linux 上也能工作吗?** +A: 当然可以。`Paths.get` 调用抽象了操作系统特定的分隔符,且 Aspose.HTML 是跨平台的。 + +**Q: 我可以使用相同的 API 转换其他标记语言(例如 AsciiDoc)吗?** +A: `Converter.convert` 方法开箱即支持 HTML、CSS 和 Markdown。对于 AsciiDoc,你需要先将其转换为 HTML(例如使用 AsciidoctorJ),然后将 HTML 输入到 Aspose。 + +**Q: Aspose.HTML 有免费版本吗?** +A: Aspose 提供 30 天的评估许可证,具备完整功能。生产环境使用需要商业许可证。 + +## 结论 – 你已掌握在 Java 中从 Markdown 创建 PDF + +我们已经从问题陈述——*如何从 markdown 创建 PDF?*——带你走过简洁、可运行的解决方案,并进一步到批量处理和 Web 服务等真实场景。通过利用 Aspose.HTML 的 `Converter.convert` 方法,你可以仅用几行代码 **convert markdown to pdf**,同时仍保留自定义页面尺寸、页眉、页脚和性能设置的灵活性。 + +下一步?尝试用自定义样式表替换默认的 `PdfSaveOptions`,实验嵌入字体,或将转换挂接到 CI 流水线,使每个 README 自动生成 PDF 构件。一旦掌握了 **java markdown to pdf** 的基础,想象力就是唯一的限制。 + +祝编码愉快,愿你的 PDF 总是如你所想完美呈现! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/chinese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/chinese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..7c67021ae --- /dev/null +++ b/html/chinese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: 如何在将 URL 转换为 PNG 时设置 DPI。学习使用 Aspose.HTML 在 Java 中将 HTML 渲染为 PNG、设置视口大小以及将 + HTML 保存为 PNG。 +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: zh +og_description: 如何在将 URL 转换为 PNG 时设置 DPI。一步步指南,教您使用 Aspose.HTML 将 HTML 渲染为 PNG、控制视口大小,并将 + HTML 保存为 PNG。 +og_title: 如何设置 DPI – 使用 AsposeHTML 将 HTML 渲染为 PNG +tags: +- AsposeHTML +- Java +- image rendering +title: 如何设置 DPI – 使用 AsposeHTML 将 HTML 渲染为 PNG +url: /zh/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# 如何设置 DPI – 使用 AsposeHTML 将 HTML 渲染为 PNG + +有没有想过 **如何设置 DPI** 来生成类似截图的网页图像?也许你需要 300 DPI 的 PNG 用于打印,或者为移动应用准备低分辨率的缩略图。无论哪种情况,关键是告诉渲染引擎你想要的逻辑 DPI,然后让它完成繁重的工作。 + +在本教程中,我们将使用一个实时 URL,将其渲染为 PNG 文件,**设置视口大小**,调整 DPI,最后 **将 HTML 保存为 PNG**——全部使用 Aspose.HTML for Java。无需外部浏览器,无需繁琐的命令行工具——只需干净的 Java 代码,直接放入任意 Maven 或 Gradle 项目中。 + +> **小贴士:** 如果你只需要快速生成缩略图,可以保持 DPI 为 96 DPI(大多数屏幕的默认值)。如果是用于打印的资产,请将其提升至 300 DPI 或更高。 + +![如何设置 DPI 示例](https://example.com/images/how-to-set-dpi.png "如何设置 DPI 示例") + +## 你需要准备的东西 + +- **Java 17**(或任何近期的 JDK)。 +- **Aspose.HTML for Java** 24.10 或更高版本。可以从 Maven Central 获取: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- 需要网络连接以获取目标页面(示例使用 `https://example.com/sample.html`)。 +- 对输出文件夹的写入权限。 + +就这些——不需要 Selenium,不需要无头 Chrome。Aspose.HTML 在进程内完成渲染,这意味着你始终在 JVM 中运行,避免了启动浏览器的开销。 + +## 第 1 步 – 从 URL 加载 HTML 文档 + +首先我们创建一个指向要捕获页面的 `HTMLDocument` 实例。构造函数会自动下载 HTML、解析并准备 DOM。 + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*为什么这很重要:* 直接加载文档可以省去单独的 HTTP 客户端。Aspose.HTML 会遵循重定向、Cookie,甚至在 URL 中嵌入凭据时支持基本身份验证。 + +## 第 2 步 – 构建具有期望 DPI 和视口的沙盒 + +**sandbox** 是 Aspose.HTML 用来模拟浏览器环境的方式。在这里我们让它假装是 1280 × 720 的屏幕,并且关键是设置 **device DPI**。更改 DPI 会改变渲染图像的像素密度,而不会改变逻辑尺寸。 + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*为什么可能需要调整这些值:* +- **视口大小** 决定 CSS 媒体查询(`@media (max-width: …)`)的行为。 +- **设备 DPI** 影响图像在打印时的实际尺寸。96 DPI 的图像在屏幕上看起来不错;300 DPI 的图像在纸张上保持清晰。 + +如果你需要正方形缩略图,只需将 `setViewportSize(500, 500)` 改为所需尺寸,并保持低 DPI。 + +## 第 3 步 – 选择 PNG 作为输出格式 + +Aspose.HTML 支持多种光栅格式(PNG、JPEG、BMP、GIF)。PNG 是无损的,非常适合需要保留每个像素的截图。 + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +如果你关心文件大小,还可以通过 `pngOptions.setCompressionLevel(9)` 调整压缩级别。 + +## 第 4 步 – 渲染并保存图像 + +现在让文档 **保存** 为图像。`save` 方法接受文件路径和前面配置好的选项。 + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +程序结束后,你会在 `YOUR_DIRECTORY/sandboxed.png` 找到 PNG 文件。打开它——如果你将 DPI 设置为 300,图像元数据会反映该 DPI,尽管像素尺寸仍为 1280 × 720。 + +## 第 5 步 – 验证 DPI(可选但实用) + +如果想再次确认 DPI 确实生效,可以使用轻量级库 **metadata‑extractor** 读取 PNG 元数据: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +控制台应打印出 `300`(或你设置的值)。此步骤并非渲染所必需,但在为打印工作流生成资产时是一个快速的 sanity check。 + +## 常见问题与边缘情况 + +### “如果页面使用 JavaScript 加载内容怎么办?” + +Aspose.HTML 执行 **受限的 JavaScript 子集**。对于大多数静态站点,它可以直接工作。如果页面严重依赖客户端框架(React、Angular、Vue),可能需要预渲染页面或改用无头浏览器。不过,一旦 DOM 准备好,设置 DPI 的方式保持不变。 + +### “我可以渲染 PDF 而不是 PNG 吗?” + +完全可以。将 `ImageSaveOptions` 替换为 `PdfSaveOptions`,并将输出扩展名改为 `.pdf`。DPI 设置仍会影响任何嵌入图像的栅格化外观。 + +### “高分辨率的 Retina 屏幕截图怎么办?” + +只需将视口尺寸加倍,同时保持 DPI 为 96 DPI,或者保持视口不变并将 DPI 提升到 192。生成的 PNG 将拥有两倍的像素量,呈现出清晰的 Retina 效果。 + +### “我需要清理资源吗?” + +`HTMLDocument` 实现了 `AutoCloseable`。在生产环境中,建议使用 try‑with‑resources 包裹: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +这样可以及时释放本机资源。 + +## 完整可运行示例(复制粘贴即用) + +下面是完整的可直接运行的程序。将 `YOUR_DIRECTORY` 替换为你机器上的实际文件夹路径。 + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +运行该类,你将得到一个遵循 **如何设置 DPI** 设置的 PNG 文件。 + +## 结论 + +我们已经演示了 **如何设置 DPI** 在 **将 HTML 渲染为 PNG** 时的完整流程,涵盖了 **设置视口大小** 步骤,并展示了如何使用 Aspose.HTML for Java **将 HTML 保存为 PNG**。关键要点如下: + +- 使用 **sandbox** 控制 DPI 和视口。 +- 选择合适的 **ImageSaveOptions** 以获得无损输出。 +- 如有需要,验证 DPI 元数据以确保打印质量。 + +接下来,你可以尝试不同的 DPI 值、更大的视口,甚至批量处理一系列 URL。想把整个网站转换为 PNG 缩略图?只需遍历 URL 数组并复用相同的 sandbox 配置。 + +祝渲染愉快,愿你的截图始终像素完美! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/chinese/java/css-html-form-editing/_index.md b/html/chinese/java/css-html-form-editing/_index.md index 9115a8686..575a33772 100644 --- a/html/chinese/java/css-html-form-editing/_index.md +++ b/html/chinese/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ url: /zh/java/css-html-form-editing/ 了解如何使用 Aspose.HTML for Java 应用高级 CSS 技术,包括自定义页边距和动态内容。面向开发人员的详细实践教程。 ### [使用 Aspose.HTML for Java 编辑和提交 HTML 表单](./html-form-editing/) 通过本全面的分步指南了解如何使用 Aspose.HTML for Java 以编程方式编辑和提交 HTML 表单。 +### [如何在 Java 中获取样式 – 加载 HTML 并使用查询选择器](./how-to-get-style-in-java-load-html-query-selector/) +本教程演示如何在 Java 中加载 HTML 并使用查询选择器获取元素样式。 + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/chinese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/chinese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..24db993f5 --- /dev/null +++ b/html/chinese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: 如何在 Java 中获取样式——学习如何加载 HTML 文档,使用查询选择器示例,并使用 Aspose.HTML 读取 background-color + 属性。 +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: zh +og_description: 如何在 Java 中获取样式——一步步指南,加载 HTML 文档,运行 query selector 示例,并获取 background-color + 属性。 +og_title: 如何在 Java 中获取样式 – 加载 HTML 并使用查询选择器 +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: 如何在 Java 中获取样式——加载 HTML 与查询选择器 +url: /zh/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# 如何在 Java 中获取样式 – 加载 HTML 并使用查询选择器 + +是否曾经好奇在使用 Java 解析 HTML 时**如何获取元素的样式**?也许你在构建爬虫、测试工具,或只是需要验证生成页面中的视觉提示。好消息是 Aspose.HTML 能让这件事轻而易举。在本教程中,我们将演示如何加载 HTML 文档、使用**查询选择器示例**,以及最终读取 `
` 元素的**background-color 属性**。没有魔法,只有可以直接复制粘贴运行的清晰 Java 代码。 + +## 您需要的环境 + +在开始之前,请确保拥有: + +* **Java 17**(或任意近期 JDK)——API 支持 Java 8+,但更新的版本性能更佳。 +* **Aspose.HTML for Java** 库——可从 Maven Central 获取(本文撰写时为 `com.aspose:aspose-html:23.10`)。 +* 一个小型 HTML 文件(`input.html`),其中至少包含一个设置了 CSS `background-color`(无论是内联还是通过样式表)的 `
`。 + +就这些。无需额外框架、沉重的浏览器,只需纯 Java 与 Aspose.HTML。 + +## 步骤 1:加载 HTML 文档 + +首先要**加载 HTML 文档**到内存中。Aspose.HTML 的 `HTMLDocument` 类封装了文件系统处理,并为你提供可查询的 DOM。 + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **为什么重要:** 加载文档会创建已解析的 DOM 树,这是后续任何 CSS 或 JavaScript 求值的基础。如果文件未找到,Aspose 会抛出描述性的 `FileNotFoundException`,请务必检查路径。 + +### 专业提示 +如果你是从 URL 而非本地文件获取 HTML,只需将 URL 字符串传给构造函数——Aspose 会为你处理 HTTP 请求。 + +## 步骤 2:使用查询选择器示例 + +文档已在内存中后,使用**查询选择器示例**来获取第一个 `
` 元素。`querySelector` 方法遵循你在浏览器中已经熟悉的 CSS 选择器语法。 + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **为什么重要:** `querySelector` 返回第一个匹配的节点,当你只需要单个元素的样式时非常合适。如果需要多个元素,`querySelectorAll` 会返回 `NodeList`。 + +### 边缘情况 +如果选择器未匹配到任何内容,`divElement` 将为 `null`。在读取样式之前务必进行空值检查: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## 步骤 3:获取计算后的样式 + +拿到元素后,下一步是**解析 HTML Java**以计算最终的 CSS 值。Aspose.HTML 完成繁重工作:它会解析层叠、继承,甚至外部样式表。 + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **为什么重要:** 计算后的样式反映了浏览器在处理所有 CSS 规则后实际会应用的值。它比直接读取 `style` 属性更可靠,因为后者可能不完整。 + +## 步骤 4:检索 background‑color 属性 + +最后,提取我们关心的**background-color 属性**。`getPropertyValue` 方法以字符串形式返回该值(例如 `rgba(255, 0, 0, 1)`)。 + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **你将看到的结果:** 如果你的 `
` 通过内联或样式表设置了 `background-color: #ff5733;`,控制台会输出类似 `Computed background‑color: rgb(255, 87, 51)`。 + +### 常见陷阱 +当属性未定义时,`getPropertyValue` 返回空字符串。这时可以回退到默认值,或检查父元素的样式。 + +## 完整可运行示例 + +将上述步骤整合,得到完整的可直接运行程序: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**预期输出(示例):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +如果 `
` 没有设置背景颜色,输出将为空行——这正是提示你检查继承样式的信号。 + +## 提示、技巧及注意事项 + +| 情况 | 处理方法 | +|-----------|------------| +| **多个 `
` 元素** | 使用 `querySelectorAll("div")` 并遍历返回的 `NodeList`。 | +| **外部 CSS 文件** | 确保 HTML 文件正确引用了它们的路径;Aspose.HTML 会自动获取。 | +| **仅有内联 `style` 属性** | `getComputedStyle` 仍然有效——它会将内联样式与默认值合并。 | +| **性能关注** | 文档只需加载一次,若需查询大量元素,请复用 `HTMLDocument` 实例。 | +| **在 Android 上运行** | Aspose.HTML for Java 支持 Android,但需引入 Android 专用的 AAR 包。 | + +## 您可能感兴趣的相关主题 + +* **使用 Jsoup 与 Aspose.HTML 解析 HTML 的对比** – 何时选择哪一个。 +* **将计算后的样式导出为 JSON** – 对 API 驱动的前端非常有用。 +* **自动化截图生成** – 将计算样式与 Aspose.PDF 结合,用于视觉回归测试。 + +--- + +### 结论 + +现在,你已经掌握了在使用 Aspose.HTML **加载 HTML 文档**、执行 **查询选择器示例**,并提取 **background-color 属性**的完整流程。代码自包含,可在任意近期 JDK 上运行,并能优雅地处理缺失元素或未定义样式。从这里你可以进一步获取字体大小、外边距,甚至在执行 JavaScript 后的计算值(Aspose.HTML 也支持脚本求值)。 + +动手试一试,调整选择器,看看还能发现哪些 CSS 宝藏。祝编码愉快! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/czech/java/conversion-html-to-various-image-formats/_index.md b/html/czech/java/conversion-html-to-various-image-formats/_index.md index 8a2056cb9..ae558d76b 100644 --- a/html/czech/java/conversion-html-to-various-image-formats/_index.md +++ b/html/czech/java/conversion-html-to-various-image-formats/_index.md @@ -92,6 +92,7 @@ Naučte se převést HTML do JPEG pomocí Aspose.HTML for Java. Krok‑za‑krok Naučte se převést HTML na PNG obrázky v Javě pomocí Aspose.HTML. Komplexní průvodce s krok‑za‑krokem instrukcemi. ### [Převod HTML do TIFF](./convert-html-to-tiff/) Naučte se snadno převést HTML do TIFF pomocí Aspose.HTML for Java. Krok‑za‑krokem průvodce pro efektivní zpracování dokumentů. +### [Jak nastavit DPI – Renderovat HTML do PNG pomocí AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) ## Často kladené otázky diff --git a/html/czech/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/czech/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..170d3cac8 --- /dev/null +++ b/html/czech/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,225 @@ +--- +category: general +date: 2026-01-14 +description: jak nastavit DPI při převodu URL na PNG. Naučte se renderovat HTML do + PNG, nastavit velikost viewportu a uložit HTML jako PNG pomocí Aspose.HTML v Javě. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: cs +og_description: Jak nastavit DPI při převodu URL na PNG. Krok za krokem návod, jak + renderovat HTML do PNG, ovládat velikost viewportu a uložit HTML jako PNG pomocí + Aspose.HTML. +og_title: jak nastavit dpi – Vykreslit HTML do PNG pomocí AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: jak nastavit DPI – renderovat HTML do PNG pomocí AsposeHTML +url: /cs/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# jak nastavit dpi – Render HTML do PNG s AsposeHTML + +Už jste se někdy zamysleli **nad tím, jak nastavit dpi** pro obrázek podobný snímku obrazovky generovaný z webové stránky? Možná potřebujete PNG s 300 DPI pro tisk, nebo nízké rozlišení miniatury pro mobilní aplikaci. V obou případech je trik v tom, že řeknete vykreslovacímu enginu, jaké logické DPI chcete, a nechte ho udělat těžkou práci. + +V tomto tutoriálu vezmeme živou URL, vykreslíme ji do souboru PNG, **nastavíme velikost viewportu**, upravíme DPI a nakonec **uložíme HTML jako PNG**—vše pomocí Aspose.HTML pro Java. Žádné externí prohlížeče, žádné nešikovné nástroje z příkazové řádky—pouze čistý Java kód, který můžete vložit do libovolného Maven nebo Gradle projektu. + +> **Pro tip:** Pokud potřebujete jen rychlou miniaturu, můžete nechat DPI na 96 DPI (výchozí pro většinu obrazovek). Pro tiskové soubory zvyšte na 300 DPI nebo více. + +![příklad nastavení dpi](https://example.com/images/how-to-set-dpi.png "příklad nastavení dpi") + +## Co budete potřebovat + +- **Java 17** (nebo jakýkoli novější JDK). +- **Aspose.HTML for Java** 24.10 nebo novější. Můžete jej získat z Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Internetové připojení pro stažení cílové stránky (příklad používá `https://example.com/sample.html`). +- Oprávnění k zápisu do výstupního adresáře. + +A to je vše—žádný Selenium, žádný headless Chrome. Aspose.HTML provádí vykreslování v‑procesu, což znamená, že zůstáváte uvnitř JVM a vyhnete se režii spouštění prohlížeče. + +## Krok 1 – Načtení HTML dokumentu z URL + +Nejprve vytvoříme instanci `HTMLDocument`, která ukazuje na stránku, kterou chceme zachytit. Konstruktor automaticky stáhne HTML, parsuje jej a připraví DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Proč je to důležité:* Načtením dokumentu přímo vynecháte potřebu samostatného HTTP klienta. Aspose.HTML respektuje přesměrování, cookies a dokonce i základní autentifikaci, pokud vložíte přihlašovací údaje do URL. + +## Krok 2 – Vytvoření sandboxu s požadovaným DPI a viewportem + +**Sandbox** je způsob, jakým Aspose.HTML napodobuje prostředí prohlížeče. Zde mu říkáme, aby se tvářil jako obrazovka 1280 × 720 a, co je klíčové, nastavíme **DPI zařízení**. Změna DPI mění hustotu pixelů vykresleného obrázku, aniž by změnila logickou velikost. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Proč byste mohli tyto hodnoty upravit:* +- **Velikost viewportu** řídí, jak se chovají CSS media queries (`@media (max-width: …)`). +- **DPI zařízení** ovlivňuje fyzickou velikost obrázku při tisku. Obrázek s 96 DPI vypadá dobře na obrazovkách; obrázek s 300 DPI si zachovává ostrost na papíře. + +Pokud potřebujete čtvercovou miniaturu, jednoduše změňte `setViewportSize(500, 500)` a nechte DPI nízké. + +## Krok 3 – Výběr PNG jako výstupního formátu + +Aspose.HTML podporuje několik rastrových formátů (PNG, JPEG, BMP, GIF). PNG je bezztrátový, což ho činí ideálním pro snímky obrazovky, kde chcete zachovat každý pixel. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Můžete také upravit úroveň komprese (`pngOptions.setCompressionLevel(9)`), pokud vás zajímá velikost souboru. + +## Krok 4 – Vykreslení a uložení obrázku + +Nyní řekneme dokumentu, aby se **uložil** jako obrázek. Metoda `save` přijímá cestu k souboru a dříve nakonfigurované možnosti. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Po dokončení programu najdete soubor PNG v `YOUR_DIRECTORY/sandboxed.png`. Otevřete jej—pokud jste nastavili DPI na 300, metadata obrázku to odrazí, i když rozměry pixelů zůstávají 1280 × 720. + +## Krok 5 – Ověření DPI (volitelné, ale užitečné) + +Pokud chcete dvojitě zkontrolovat, že DPI bylo skutečně použito, můžete přečíst metadata PNG pomocí lehké knihovny jako **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Měli byste vidět `300` (nebo jakoukoliv hodnotu, kterou jste nastavili) vytištěnou do konzole. Tento krok není pro vykreslování vyžadován, ale je to rychlá kontrola, zejména když generujete soubory pro tiskový workflow. + +## Časté otázky a okrajové případy + +### „Co když stránka používá JavaScript k načtení obsahu?“ + +Aspose.HTML spouští **omezenou podmnožinu** JavaScriptu. Pro většinu statických stránek funguje ihned. Pokud stránka silně závisí na klientských frameworkech (React, Angular, Vue), možná budete muset stránku předem vykreslit nebo místo toho použít headless prohlížeč. Nastavení DPI však funguje stejně, jakmile je DOM připraven. + +### „Mohu místo PNG vykreslit PDF?“ + +Určitě. Vyměňte `ImageSaveOptions` za `PdfSaveOptions` a změňte výstupní příponu na `.pdf`. Nastavení DPI stále ovlivňuje rastrový vzhled všech vložených obrázků. + +### „Co vysoké rozlišení snímků pro retina displeje?“ + +Jednoduše zdvojnásobte rozměry viewportu při zachování DPI na 96 DPI, nebo ponechte viewport a zvýšte DPI na 192. Výsledný PNG bude obsahovat dvakrát více pixelů, což vám poskytne ostrý retina vzhled. + +### „Musím uvolňovat prostředky?“ + +`HTMLDocument` implements `AutoCloseable`. In a production app, wrap it in a try‑with‑resources block: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +To zajistí, že nativní prostředky budou uvolněny okamžitě. + +## Kompletní funkční příklad (připravený ke kopírování) + +Níže je kompletní program připravený ke spuštění. Nahraďte `YOUR_DIRECTORY` skutečným adresářem na vašem počítači. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Spusťte třídu a získáte PNG, který respektuje nastavení **jak nastavit dpi**, které jste zadali. + +## Závěr + +Prošli jsme **jak nastavit dpi** při **vykreslování HTML do PNG**, pokryli krok **nastavení velikosti viewportu** a ukázali vám, jak **uložit HTML jako PNG** pomocí Aspose.HTML pro Java. Hlavní body jsou: + +- Použijte **sandbox** k řízení DPI a viewportu. +- Vyberte správné **ImageSaveOptions** pro bezztrátový výstup. +- Ověřte metadata DPI, pokud potřebujete zajistit kvalitu tisku. + +Odtud můžete experimentovat s různými hodnotami DPI, většími viewporty nebo dokonce hromadně zpracovávat seznam URL. Chcete převést celý web na PNG miniatury? Stačí projít pole URL a znovu použít stejnou konfiguraci sandboxu. + +Šťastné vykreslování a ať jsou vaše snímky obrazovky vždy pixel‑dokonalé! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/dutch/java/conversion-html-to-various-image-formats/_index.md b/html/dutch/java/conversion-html-to-various-image-formats/_index.md index 1e5af21fe..0ce5c8ea7 100644 --- a/html/dutch/java/conversion-html-to-various-image-formats/_index.md +++ b/html/dutch/java/conversion-html-to-various-image-formats/_index.md @@ -97,6 +97,8 @@ Leer HTML naar JPEG te converteren met Aspose.HTML for Java. Stap‑voor‑stap Leer hoe je HTML naar PNG‑afbeeldingen kunt converteren in Java met Aspose.HTML. Een uitgebreide gids met stap‑voor‑stap instructies. ### [HTML naar TIFF converteren](./convert-html-to-tiff/) Leer hoe je HTML eenvoudig naar TIFF kunt converteren met Aspose.HTML for Java. Stap‑voor‑stap gids voor efficiënte documentafhandeling. +### [Hoe DPI instellen – HTML renderen naar PNG met AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Leer hoe je de DPI-waarde kunt aanpassen bij het renderen van HTML naar PNG met Aspose.HTML for Java. ## Veelgestelde vragen diff --git a/html/dutch/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/dutch/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..e835d577a --- /dev/null +++ b/html/dutch/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: hoe DPI in te stellen bij het converteren van een URL naar PNG. Leer + HTML naar PNG te renderen, de viewportgrootte in te stellen en HTML op te slaan + als PNG met Aspose.HTML in Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: nl +og_description: hoe DPI in te stellen bij het converteren van een URL naar PNG. Stapsgewijze + handleiding om HTML naar PNG te renderen, de viewportgrootte te regelen en HTML + op te slaan als PNG met Aspose.HTML. +og_title: Hoe DPI in te stellen – HTML renderen naar PNG met AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: hoe DPI in te stellen – HTML renderen naar PNG met AsposeHTML +url: /nl/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# hoe DPI in te stellen – HTML renderen naar PNG met AsposeHTML + +Heb je je ooit afgevraagd **hoe je DPI instelt** voor een screenshot‑achtig beeld dat van een webpagina wordt gegenereerd? Misschien heb je een 300 DPI PNG nodig voor afdrukken, of een lage‑res thumbnail voor een mobiele app. In beide gevallen is de truc om de renderengine te vertellen welke logische DPI je wilt, en het vervolgens het zware werk te laten doen. + +In deze tutorial nemen we een live URL, renderen we deze naar een PNG‑bestand, **stellen we de viewport‑grootte in**, passen we de DPI aan, en slaan we tenslotte **HTML op als PNG**—alles met Aspose.HTML voor Java. Geen externe browsers, geen rommelige command‑line tools—gewoon nette Java‑code die je in elk Maven‑ of Gradle‑project kunt gebruiken. + +> **Pro tip:** Als je alleen een snelle thumbnail wilt, kun je de DPI op 96 DPI houden (de standaard voor de meeste schermen). Voor print‑klare assets, verhoog je deze naar 300 DPI of hoger. + +![voorbeeld hoe DPI in te stellen](https://example.com/images/how-to-set-dpi.png "voorbeeld hoe DPI in te stellen") + +## Wat je nodig hebt + +- **Java 17** (of een recente JDK). +- **Aspose.HTML for Java** 24.10 of nieuwer. Je kunt het ophalen van Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Een internetverbinding om de doelpagina op te halen (het voorbeeld gebruikt `https://example.com/sample.html`). +- Schrijfrechten voor de doelmap. + +Dat is alles—geen Selenium, geen headless Chrome. Aspose.HTML doet de rendering in‑process, wat betekent dat je binnen de JVM blijft en de overhead van het starten van een browser vermijdt. + +## Stap 1 – Laad het HTML‑document vanaf een URL + +Eerst maken we een `HTMLDocument`‑instantie die naar de pagina wijst die we willen vastleggen. De constructor downloadt automatisch de HTML, parseert deze en bereidt de DOM voor. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Waarom dit belangrijk is:* Door het document direct te laden, hoef je geen aparte HTTP‑client te gebruiken. Aspose.HTML respecteert redirects, cookies, en zelfs basisauthenticatie als je inloggegevens in de URL opneemt. + +## Stap 2 – Bouw een sandbox met gewenste DPI en viewport + +Een **sandbox** is de manier waarop Aspose.HTML een browser‑omgeving nabootst. Hier laten we het doen alsof het een 1280 × 720 scherm is en, cruciaal, stellen we de **apparaat‑DPI** in. Het wijzigen van de DPI verandert de pixel‑dichtheid van de gerenderde afbeelding zonder de logische grootte aan te passen. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Waarom je deze waarden zou kunnen aanpassen:* +- **Viewport‑grootte** bepaalt hoe CSS‑media‑queries (`@media (max-width: …)`) zich gedragen. +- **Apparaat‑DPI** beïnvloedt de fysieke grootte van de afbeelding bij afdrukken. Een 96 DPI afbeelding ziet er goed uit op schermen; een 300 DPI afbeelding behoudt scherpte op papier. + +Als je een vierkante thumbnail nodig hebt, wijzig je eenvoudig `setViewportSize(500, 500)` en houd je de DPI laag. + +## Stap 3 – Kies PNG als uitvoerformaat + +Aspose.HTML ondersteunt verschillende rasterformaten (PNG, JPEG, BMP, GIF). PNG is loss‑less, waardoor het perfect is voor screenshots waarbij je elke pixel wilt behouden. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Je kunt ook het compressieniveau aanpassen (`pngOptions.setCompressionLevel(9)`) als je je zorgen maakt over de bestandsgrootte. + +## Stap 4 – Render en sla de afbeelding op + +Nu laten we het document zichzelf **opslaan** als afbeelding. De `save`‑methode neemt een bestandspad en de eerder geconfigureerde opties. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Wanneer het programma klaar is, vind je een PNG‑bestand op `YOUR_DIRECTORY/sandboxed.png`. Open het—als je de DPI op 300 hebt ingesteld, zal de afbeeldingsmetadata dat weergeven, hoewel de pixelafmetingen 1280 × 720 blijven. + +## Stap 5 – Verifieer de DPI (optioneel maar handig) + +Als je wilt dubbel‑controleren of de DPI echt is toegepast, kun je de PNG‑metadata lezen met een lichte bibliotheek zoals **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Je zou `300` (of wat je ook hebt ingesteld) in de console moeten zien verschijnen. Deze stap is niet vereist voor het renderen, maar het is een snelle sanity‑check, vooral wanneer je assets genereert voor een print‑workflow. + +## Veelgestelde vragen & randgevallen + +### “Wat als de pagina JavaScript gebruikt om inhoud te laden?” + +Aspose.HTML voert een **beperkte subset** van JavaScript uit. Voor de meeste statische sites werkt het direct. Als de pagina sterk afhankelijk is van client‑side frameworks (React, Angular, Vue), moet je de pagina mogelijk vooraf renderen of een headless browser gebruiken. Het instellen van DPI werkt echter op dezelfde manier zodra de DOM klaar is. + +### “Kan ik een PDF renderen in plaats van PNG?” + +Zeker. Vervang `ImageSaveOptions` door `PdfSaveOptions` en wijzig de uitvoerextensie naar `.pdf`. De DPI‑instelling beïnvloedt nog steeds het gerasterde uiterlijk van eventuele ingesloten afbeeldingen. + +### “Wat betreft high‑resolution screenshots voor retina‑displays?” + +Verdubbel simpelweg de viewport‑afmetingen terwijl je de DPI op 96 DPI houdt, of behoud de viewport en verhoog de DPI naar 192. De resulterende PNG bevat dan twee keer zoveel pixels, waardoor je dat scherpe retina‑gevoel krijgt. + +### “Moet ik resources opruimen?” + +`HTMLDocument` implementeert `AutoCloseable`. In een productie‑app, wikkel het in een try‑with‑resources‑blok: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## Volledig werkend voorbeeld (klaar om te kopiëren‑plakken) + +Hieronder staat het volledige, kant‑klaar programma. Vervang `YOUR_DIRECTORY` door een echte map op jouw machine. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Voer de klasse uit, en je krijgt een PNG die de **hoe DPI in te stellen**‑instelling die je hebt opgegeven respecteert. + +## Conclusie + +We hebben stap voor stap uitgelegd **hoe je DPI instelt** wanneer je **HTML rendert naar PNG**, de stap **viewport‑grootte instellen** behandeld, en laten zien hoe je **HTML opslaat als PNG** met Aspose.HTML voor Java. De belangrijkste punten zijn: + +- Gebruik een **sandbox** om DPI en viewport te controleren. +- Kies de juiste **ImageSaveOptions** voor lossless output. +- Verifieer de DPI‑metadata als je printkwaliteit moet garanderen. + +Vanaf hier kun je experimenteren met verschillende DPI‑waarden, grotere viewports, of zelfs een batch‑verwerking van een lijst URL's. Wil je een hele website omzetten naar PNG‑thumbnails? Loop gewoon over een array van URL's en hergebruik dezelfde sandbox‑configuratie. + +Veel renderplezier, en moge je screenshots altijd pixel‑perfect zijn! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/english/java/conversion-html-to-other-formats/_index.md b/html/english/java/conversion-html-to-other-formats/_index.md index 9ed046554..970bd4ee7 100644 --- a/html/english/java/conversion-html-to-other-formats/_index.md +++ b/html/english/java/conversion-html-to-other-formats/_index.md @@ -89,6 +89,8 @@ Effortlessly convert HTML to MHTML using Aspose.HTML for Java. Follow our step-b Learn how to effortlessly convert HTML to XPS using Aspose.HTML for Java. Create cross-platform documents with ease. ### [Converting Markdown to HTML](./convert-markdown-to-html/) Convert Markdown to HTML in Java seamlessly with Aspose.HTML for Java. Follow our step-by-step guide to streamline your document conversion needs. +### [Create PDF from Markdown in Java – Simple One‑Liner Guide](./create-pdf-from-markdown-in-java-simple-one-liner-guide/) +Generate a PDF directly from Markdown in Java with a single line of code using Aspose.HTML. ### [Converting SVG to Image](./convert-svg-to-image/) Learn how to convert SVG to images in Java with Aspose.HTML. Comprehensive guide for high-quality output. ### [Converting SVG to PDF](./convert-svg-to-pdf/) @@ -124,4 +126,4 @@ A: Yes. You can set title, author, subject, and keywords via the `PdfSaveOptions {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/english/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/english/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..c1f0b1eaf --- /dev/null +++ b/html/english/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Create PDF from Markdown in Java using Aspose.HTML – a quick step‑by‑step + tutorial to convert markdown to pdf, save markdown as pdf, and learn java markdown + to pdf basics. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: en +og_description: Create PDF from Markdown in Java with Aspose.HTML. Learn how to convert + markdown to pdf, save markdown as pdf, and handle common edge cases in a concise + tutorial. +og_title: Create PDF from Markdown in Java – Quick One‑Liner +tags: +- Java +- PDF +- Markdown +title: Create PDF from Markdown in Java – Simple One‑Liner Guide +url: /java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Create PDF from Markdown in Java – Simple One‑Liner Guide + +Ever wondered how to **create PDF from Markdown** without wrestling with dozens of libraries? You're not alone. Many developers need to turn their `.md` notes into polished PDFs for reports, documentation, or e‑books, and they want a solution that works in a single line of Java code. + +In this tutorial we’ll walk through exactly that: using the Aspose.HTML for Java library to **convert markdown to pdf** and **save markdown as pdf** in a clean, maintainable way. We'll also touch on the broader topic of **java markdown to pdf** so you understand the why behind each step, not just the how. + +> **What you'll walk away with** +> A complete, runnable Java program that reads `input.md`, writes `output.pdf`, and prints a friendly success message. Plus, you’ll know how to tweak the conversion, handle missing files, and integrate the code into larger projects. + +## Prerequisites – What You Need Before You Start + +- **Java Development Kit (JDK) 11 or newer** – the code uses `java.nio.file.Paths`, which is available since JDK 7, but JDK 11 is the current LTS and ensures compatibility with Aspose.HTML. +- **Aspose.HTML for Java** (version 23.9 or later). You can grab it from Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **A Markdown file** (`input.md`) placed somewhere you can reference. If you don’t have one, create a tiny file with a couple of headings and a list – the library will handle any valid Markdown. +- **An IDE or plain `javac`/`java`** – we’ll keep the code pure Java, no Spring or other frameworks required. + +> **Pro tip:** If you’re using Maven, add the dependency to your `pom.xml` and run `mvn clean install`. If you prefer Gradle, the equivalent is `implementation 'com.aspose:aspose-html:23.9'`. + +## Overview – Create PDF from Markdown in One Shot + +Below is the full program we’ll build. Notice the **single call** to `Converter.convert(...)`; that’s the heart of the **create pdf from markdown** operation. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Running this class will read `input.md`, generate `output.pdf`, and output the confirmation line. That’s it—**the entire `create pdf from markdown` workflow in under 30 lines** (including comments). + +## Step‑by‑Step Breakdown + +### 1️⃣ Define the Source and Destination Files + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Why we use `Paths.get`**: It builds an OS‑independent path, handling Windows backslashes and Unix forward slashes automatically. +- **Edge case**: If the Markdown file does not exist, `Converter.convert` throws a `FileNotFoundException`. You can pre‑check with `Files.exists(Paths.get(markdownPath))` and give a friendly error. + +### 2️⃣ Set Up PDF Save Options (Optional Tweaks) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Default behavior**: The PDF will use A4 page size, default margins, and embed fonts automatically. +- **Customizing**: Want a landscape layout? Use `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Performance tip**: For large Markdown files, you can enable `pdfOptions.setEmbedStandardFonts(false)` to reduce file size at the cost of potential rendering differences. + +### 3️⃣ Perform the Conversion – The Heart of “Convert Markdown to PDF” + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **What happens under the hood**: Aspose.HTML parses the Markdown into an internal HTML DOM, then renders that DOM to PDF using its high‑fidelity layout engine. +- **Why this is the recommended approach**: Compared to hand‑rolled HTML‑to‑PDF pipelines (e.g., using wkhtmltopdf), Aspose handles CSS, tables, images, and Unicode out of the box, making the **how to convert markdown** question trivial. + +### 4️⃣ Confirmation Message + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +A tiny UX touch—especially useful when the program runs as part of a larger batch job. + +## Handling Common Pitfalls + +| Issue | Symptom | Fix | +|-------|---------|-----| +| **Missing Markdown file** | `FileNotFoundException` | Verify the path beforehand: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Unsupported images** | Images appear as broken placeholders in PDF | Ensure images are referenced with absolute paths or embed them as Base64 in the Markdown. | +| **Large documents cause OOM** | `OutOfMemoryError` | Increase JVM heap (`-Xmx2g`) or split the Markdown into sections and convert each separately, then merge PDFs (Aspose offers `PdfFile` merging). | +| **Special fonts missing** | Text rendered with fallback font | Install the required fonts on the host or embed them manually via `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Extending the One‑Liner: Real‑World Scenarios + +### A. Batch Conversion of Multiple Files + +If you need to **save markdown as pdf** for a whole folder, wrap the conversion in a loop: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Adding a Custom Header/Footer + +Suppose you want every page to show a logo and page number. Use `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Now each generated PDF carries the branding you need—perfect for corporate documentation. + +### C. Integrating into a Spring Boot Service + +Expose the conversion as a REST endpoint: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +Now the **java markdown to pdf** capability is available to any client—mobile, web, or desktop. + +## Expected Output + +After running the original `MdToPdfOneLiner`, you should see a new file `output.pdf` in the folder you specified. Opening it will display your Markdown content rendered with proper headings, lists, code blocks, and any images you included. The PDF is fully searchable, and text can be copied—unlike image‑only PDFs. + +## Frequently Asked Questions + +**Q: Does this work on macOS/Linux as well as Windows?** +A: Absolutely. The `Paths.get` call abstracts away OS‑specific separators, and Aspose.HTML is cross‑platform. + +**Q: Can I convert other markup languages (e.g., AsciiDoc) with the same API?** +A: The `Converter.convert` method supports HTML, CSS, and Markdown out of the box. For AsciiDoc you’d first need to transform it to HTML (e.g., using AsciidoctorJ) and then feed the HTML to Aspose. + +**Q: Is there a free version of Aspose.HTML?** +A: Aspose offers a 30‑day evaluation license with full functionality. For production use, a commercial license is required. + +## Conclusion – You’ve Mastered Creating PDF from Markdown in Java + +We’ve taken you from the problem statement—*how do I create PDF from markdown?*—through a concise, runnable solution, and on to real‑world extensions like batch processing and web services. By leveraging Aspose.HTML’s `Converter.convert` method, you can **convert markdown to pdf** with just a few lines of code, while still retaining the flexibility to customize page size, headers, footers, and performance settings. + +Next steps? Try swapping the default `PdfSaveOptions` for a custom stylesheet, experiment with embedding fonts, or hook the conversion into your CI pipeline so every README automatically gets a PDF artifact. The sky’s the limit once you’ve got the **java markdown to pdf** foundation under your belt. + +Happy coding, and may your PDFs always render exactly as you imagined! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/english/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/english/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..cd8ca65f3 --- /dev/null +++ b/html/english/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: how to set dpi when converting a URL to PNG. Learn to render HTML to + PNG, set viewport size, and save HTML as PNG using Aspose.HTML in Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: en +og_description: how to set dpi when converting a URL to PNG. Step‑by‑step guide to + render HTML to PNG, control viewport size, and save HTML as PNG using Aspose.HTML. +og_title: how to set dpi – Render HTML to PNG with AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: how to set dpi – Render HTML to PNG with AsposeHTML +url: /java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# how to set dpi – Render HTML to PNG with AsposeHTML + +Ever wondered **how to set dpi** for a screenshot‑like image generated from a web page? Maybe you need a 300 DPI PNG for print, or a low‑res thumbnail for a mobile app. In either case, the trick is to tell the rendering engine what logical DPI you want, then let it do the heavy lifting. + +In this tutorial we’ll take a live URL, render it to a PNG file, **set the viewport size**, adjust the DPI, and finally **save HTML as PNG**—all with Aspose.HTML for Java. No external browsers, no messy command‑line tools—just clean Java code you can drop into any Maven or Gradle project. + +> **Pro tip:** If you’re only after a quick thumbnail, you can keep the DPI at 96 DPI (the default for most screens). For print‑ready assets, bump it up to 300 DPI or higher. + +![how to set dpi example](https://example.com/images/how-to-set-dpi.png "how to set dpi example") + +## What You’ll Need + +- **Java 17** (or any recent JDK). +- **Aspose.HTML for Java** 24.10 or newer. You can grab it from Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- An internet connection to fetch the target page (the example uses `https://example.com/sample.html`). +- Write permission to the output folder. + +That’s it—no Selenium, no headless Chrome. Aspose.HTML does the rendering in‑process, which means you stay inside the JVM and avoid the overhead of launching a browser. + +## Step 1 – Load the HTML Document from a URL + +First we create an `HTMLDocument` instance pointing at the page we want to capture. The constructor automatically downloads the HTML, parses it, and prepares the DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Why this matters:* By loading the document directly, you skip the need for a separate HTTP client. Aspose.HTML respects redirects, cookies, and even basic authentication if you embed credentials in the URL. + +## Step 2 – Build a Sandbox with Desired DPI and Viewport + +A **sandbox** is Aspose.HTML’s way of mimicking a browser environment. Here we tell it to pretend it’s a 1280 × 720 screen and, crucially, we set the **device DPI**. Changing the DPI changes the pixel density of the rendered image without altering the logical size. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Why you might tweak these values:* +- **Viewport size** controls how CSS media queries (`@media (max-width: …)`) behave. +- **Device DPI** influences the physical size of the image when printed. A 96 DPI image looks fine on screens; a 300 DPI image retains crispness on paper. + +If you need a square thumbnail, simply change `setViewportSize(500, 500)` and keep the DPI low. + +## Step 3 – Choose PNG as the Output Format + +Aspose.HTML supports several raster formats (PNG, JPEG, BMP, GIF). PNG is loss‑less, which makes it perfect for screenshots where you want every pixel preserved. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +You can also tweak compression level (`pngOptions.setCompressionLevel(9)`) if you’re concerned about file size. + +## Step 4 – Render and Save the Image + +Now we tell the document to **save** itself as an image. The `save` method takes a file path and the previously configured options. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +When the program finishes, you’ll find a PNG file at `YOUR_DIRECTORY/sandboxed.png`. Open it—if you set the DPI to 300, the image metadata will reflect that, even though the pixel dimensions remain 1280 × 720. + +## Step 5 – Verify the DPI (Optional but Handy) + +If you want to double‑check that the DPI was really applied, you can read the PNG metadata with a lightweight library like **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +You should see `300` (or whatever you set) printed to the console. This step isn’t required for rendering, but it’s a quick sanity check, especially when you’re generating assets for a print workflow. + +## Common Questions & Edge Cases + +### “What if the page uses JavaScript to load content?” + +Aspose.HTML executes a **limited subset** of JavaScript. For most static sites it works out‑of‑the‑box. If the page heavily relies on client‑side frameworks (React, Angular, Vue), you might need to pre‑render the page or use a headless browser instead. However, setting DPI works the same way once the DOM is ready. + +### “Can I render a PDF instead of PNG?” + +Absolutely. Swap `ImageSaveOptions` for `PdfSaveOptions` and change the output extension to `.pdf`. The DPI setting still influences the rasterized appearance of any embedded images. + +### “What about high‑resolution screenshots for retina displays?” + +Just double the viewport dimensions while keeping the DPI at 96 DPI, or keep the viewport and bump the DPI to 192. The resulting PNG will contain twice as many pixels, giving you that crisp retina feel. + +### “Do I need to clean up resources?” + +`HTMLDocument` implements `AutoCloseable`. In a production app, wrap it in a try‑with‑resources block: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +That ensures native resources are released promptly. + +## Full Working Example (Copy‑Paste Ready) + +Below is the complete, ready‑to‑run program. Replace `YOUR_DIRECTORY` with an actual folder on your machine. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Run the class, and you’ll get a PNG that respects the **how to set dpi** setting you specified. + +## Conclusion + +We’ve walked through **how to set dpi** when you **render HTML to PNG**, covered the **set viewport size** step, and showed you how to **save HTML as PNG** using Aspose.HTML for Java. The key takeaways are: + +- Use a **sandbox** to control DPI and viewport. +- Choose the right **ImageSaveOptions** for lossless output. +- Verify the DPI metadata if you need to guarantee print quality. + +From here you can experiment with different DPI values, larger viewports, or even batch‑process a list of URLs. Want to convert a whole website into PNG thumbnails? Just loop over an array of URLs and reuse the same sandbox configuration. + +Happy rendering, and may your screenshots always be pixel‑perfect! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/english/java/css-html-form-editing/_index.md b/html/english/java/css-html-form-editing/_index.md index 00e00988e..9cc0f9dc2 100644 --- a/html/english/java/css-html-form-editing/_index.md +++ b/html/english/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ Now, let’s shift gears and explore how to effectively edit and submit HTML for Learn how to use Aspose.HTML for Java to apply advanced CSS techniques, including custom page margins and dynamic content. A detailed, hands-on tutorial for developers. ### [HTML Form Editing and Submission with Aspose.HTML for Java](./html-form-editing/) Learn how to edit and submit HTML forms programmatically using Aspose.HTML for Java in this comprehensive step-by-step guide. +### [how to get style in Java – load HTML & query selector](./how-to-get-style-in-java-load-html-query-selector/) +Learn how to load HTML in Java and retrieve CSS styles using query selectors with Aspose.HTML. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/english/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/english/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..a21329d7f --- /dev/null +++ b/html/english/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: en +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# how to get style in Java – load HTML & query selector + +Ever wondered **how to get style** of an element when you’re parsing HTML with Java? Maybe you’re building a scraper, a testing tool, or just need to verify visual cues in a generated page. The good news is that Aspose.HTML makes this a piece of cake. In this tutorial we’ll walk through loading an HTML document, using a **query selector example**, and finally reading the **background-color property** of a `
` element. No magic, just clear Java code you can copy‑paste and run. + +## What You’ll Need + +Before we dive in, make sure you have: + +* **Java 17** (or any recent JDK) – the API works with Java 8+ but newer versions give you better performance. +* **Aspose.HTML for Java** library – you can grab it from Maven Central (`com.aspose:aspose-html:23.10` as of this writing). +* A tiny HTML file (`input.html`) that contains at least one `
` with a CSS background‑color set either inline or via a stylesheet. + +That’s it. No extra frameworks, no heavyweight browsers, just plain Java and Aspose.HTML. + +## Step 1: Load the HTML Document + +The first thing you have to do is **load html document** into memory. Aspose.HTML’s `HTMLDocument` class abstracts away the file‑system handling and gives you a DOM you can query. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Why this matters:** Loading the document creates a parsed DOM tree, which is the foundation for any subsequent CSS or JavaScript evaluation. If the file can’t be found, Aspose throws a descriptive `FileNotFoundException`, so double‑check the path. + +### Pro tip +If you’re pulling HTML from a URL instead of a file, just pass the URL string to the constructor – Aspose handles the HTTP request for you. + +## Step 2: Use a Query Selector Example + +Now that the document is in memory, let’s **query selector example** to grab the first `
` element. The `querySelector` method mirrors the CSS selector syntax you already know from the browser. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Why this matters:** `querySelector` returns the first matching node, which is perfect when you only need a single element’s style. If you need multiple elements, `querySelectorAll` returns a `NodeList`. + +### Edge case +If the selector doesn’t match anything, `divElement` will be `null`. Always guard against that before you try to read styles: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Step 3: Obtain the Computed Style + +With the element in hand, the next step is to **parse html java** enough to compute the final CSS values. Aspose.HTML does the heavy lifting: it resolves cascade, inheritance, and even external stylesheets. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Why this matters:** The computed style reflects the exact values the browser would apply after processing all CSS rules. It’s more reliable than reading the raw `style` attribute, which may be incomplete. + +## Step 4: Retrieve the background‑color Property + +Finally, we pull the **background-color property** we care about. The `getPropertyValue` method returns the value as a string (e.g., `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **What you’ll see:** If your `
` had `background-color: #ff5733;` either inline or via a stylesheet, the console will output something like `Computed background‑color: rgb(255, 87, 51)`. + +### Common pitfall +When the property isn’t defined, `getPropertyValue` returns an empty string. That’s a cue to either fall back to a default or inspect the element’s parent styles. + +## Full Working Example + +Putting it all together, here’s the complete, ready‑to‑run program: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Expected output (example):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +If the `
` has no background color set, the output will be an empty line – that’s your signal to look at inherited styles. + +## Tips, Tricks, and Things to Watch Out For + +| Situation | What to Do | +|-----------|------------| +| **Multiple `
` elements** | Use `querySelectorAll("div")` and iterate over the `NodeList`. | +| **External CSS files** | Ensure the HTML file references them with correct paths; Aspose.HTML will fetch them automatically. | +| **Inline `style` attribute only** | `getComputedStyle` still works – it merges inline styles with defaults. | +| **Performance concerns** | Load the document once, reuse the `HTMLDocument` object if you need to query many elements. | +| **Running on Android** | Aspose.HTML for Java supports Android, but you’ll need to include the Android‑specific AAR. | + +## Related Topics You Might Explore + +* **Parsing HTML with Jsoup vs. Aspose.HTML** – when to pick one over the other. +* **Exporting computed styles to JSON** – useful for API‑driven front‑ends. +* **Automating screenshot generation** – combine computed styles with Aspose.PDF for visual regression testing. + +--- + +### Conclusion + +You now know **how to get style** of any element when you **load html document** with Aspose.HTML, run a **query selector example**, and extract the **background-color property**. The code is self‑contained, runs on any recent JDK, and gracefully handles missing elements or undefined styles. From here you can extend the approach to fetch font sizes, margins, or even computed values after JavaScript execution (Aspose.HTML also supports script evaluation). + +Give it a whirl, tweak the selector, and see what other CSS treasures you can uncover. Happy coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/french/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/french/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..851a40e23 --- /dev/null +++ b/html/french/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Créer un PDF à partir de Markdown en Java avec Aspose.HTML – un tutoriel + rapide étape par étape pour convertir le markdown en PDF, enregistrer le markdown + en PDF et apprendre les bases du markdown Java vers PDF. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: fr +og_description: Créez un PDF à partir de Markdown en Java avec Aspose.HTML. Apprenez + à convertir le markdown en PDF, à enregistrer le markdown en PDF et à gérer les + cas limites courants dans un tutoriel concis. +og_title: Créer un PDF à partir de Markdown en Java – One‑liner rapide +tags: +- Java +- PDF +- Markdown +title: Créer un PDF à partir de Markdown en Java – Guide simple en une ligne +url: /fr/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Créer un PDF à partir de Markdown en Java – Guide simple en une ligne + +Vous vous êtes déjà demandé comment **créer un PDF à partir de Markdown** sans vous battre avec des dizaines de bibliothèques ? Vous n'êtes pas seul. De nombreux développeurs doivent transformer leurs notes `.md` en PDF soignés pour des rapports, de la documentation ou des e‑books, et ils veulent une solution qui fonctionne en une seule ligne de code Java. + +Dans ce tutoriel, nous allons parcourir exactement cela : utiliser la bibliothèque Aspose.HTML for Java pour **convertir markdown en pdf** et **enregistrer markdown en pdf** de manière propre et maintenable. Nous aborderons également le sujet plus large du **java markdown to pdf** afin que vous compreniez le pourquoi de chaque étape, pas seulement le comment. + +> **Ce que vous en retirerez** +> Un programme Java complet et exécutable qui lit `input.md`, écrit `output.pdf` et affiche un message de succès convivial. De plus, vous saurez comment ajuster la conversion, gérer les fichiers manquants et intégrer le code dans des projets plus importants. + +## Prérequis – Ce dont vous avez besoin avant de commencer + +- **Java Development Kit (JDK) 11 ou plus récent** – le code utilise `java.nio.file.Paths`, disponible depuis JDK 7, mais JDK 11 est la LTS actuelle et assure la compatibilité avec Aspose.HTML. +- **Aspose.HTML for Java** (version 23.9 ou ultérieure). Vous pouvez le récupérer depuis Maven Central : + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **Un fichier Markdown** (`input.md`) placé quelque part où vous pouvez le référencer. Si vous n'en avez pas, créez un petit fichier avec quelques titres et une liste – la bibliothèque gérera tout Markdown valide. +- **Un IDE ou simplement `javac`/`java`** – nous garderons le code en Java pur, sans Spring ni autres frameworks requis. + +> **Astuce pro :** Si vous utilisez Maven, ajoutez la dépendance à votre `pom.xml` et exécutez `mvn clean install`. Si vous préférez Gradle, l'équivalent est `implementation 'com.aspose:aspose-html:23.9'`. + +## Vue d'ensemble – Créer un PDF à partir de Markdown en un seul passage + +Voici le programme complet que nous allons construire. Notez l'**appel unique** à `Converter.convert(...)` ; c’est le cœur de l'opération **create pdf from markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Exécuter cette classe lira `input.md`, générera `output.pdf` et affichera la ligne de confirmation. C’est tout — **l’ensemble du workflow `create pdf from markdown` en moins de 30 lignes** (commentaires inclus). + +## Décomposition étape par étape + +### 1️⃣ Définir les fichiers source et destination + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Pourquoi nous utilisons `Paths.get`** : il construit un chemin indépendant du système d'exploitation, gérant automatiquement les barres obliques inverses Windows et les barres obliques Unix. +- **Cas limite** : si le fichier Markdown n'existe pas, `Converter.convert` lève une `FileNotFoundException`. Vous pouvez pré‑vérifier avec `Files.exists(Paths.get(markdownPath))` et afficher une erreur conviviale. + +### 2️⃣ Configurer les options d’enregistrement PDF (Ajustements optionnels) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Comportement par défaut** : le PDF utilisera le format de page A4, des marges par défaut et intégrera les polices automatiquement. +- **Personnalisation** : vous voulez une mise en page paysage ? Utilisez `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Conseil de performance** : pour de gros fichiers Markdown, vous pouvez activer `pdfOptions.setEmbedStandardFonts(false)` afin de réduire la taille du fichier au prix de possibles différences de rendu. + +### 3️⃣ Effectuer la conversion – Le cœur de « Convert Markdown to PDF » + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **Ce qui se passe en coulisses** : Aspose.HTML analyse le Markdown en un DOM HTML interne, puis rend ce DOM en PDF à l'aide de son moteur de mise en page haute fidélité. +- **Pourquoi c’est l’approche recommandée** : comparé aux pipelines faits maison HTML‑to‑PDF (par ex. wkhtmltopdf), Aspose gère CSS, tableaux, images et Unicode dès le départ, rendant la question **how to convert markdown** triviale. + +### 4️⃣ Message de confirmation + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +Un petit détail UX—particulièrement utile lorsque le programme s’exécute dans le cadre d’un job batch plus important. + +## Gestion des problèmes courants + +| Problème | Symptom | Solution | +|----------|---------|----------| +| **Fichier Markdown manquant** | `FileNotFoundException` | Vérifiez le chemin au préalable : `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Images non prises en charge** | Les images apparaissent comme des espaces réservés cassés dans le PDF | Assurez‑vous que les images sont référencées avec des chemins absolus ou intégrez‑les en Base64 dans le Markdown. | +| **Documents volumineux provoquant OOM** | `OutOfMemoryError` | Augmentez le heap JVM (`-Xmx2g`) ou divisez le Markdown en sections et convertissez‑les séparément, puis fusionnez les PDF (Aspose propose la fusion avec `PdfFile`). | +| **Polices spéciales manquantes** | Texte rendu avec une police de secours | Installez les polices requises sur l’hôte ou intégrez‑les manuellement via `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Extension du One‑Liner : Scénarios réels + +### A. Conversion en lot de plusieurs fichiers + +Si vous devez **enregistrer markdown en pdf** pour un dossier entier, encapsulez la conversion dans une boucle : + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Ajout d’un en‑tête/pied de page personnalisé + +Supposons que vous vouliez que chaque page affiche un logo et le numéro de page. Utilisez `PdfSaveOptions` : + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Chaque PDF généré porte ainsi votre identité visuelle—parfait pour la documentation d’entreprise. + +### C. Intégration dans un service Spring Boot + +Exposez la conversion via un endpoint REST : + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +La capacité **java markdown to pdf** est alors disponible pour n’importe quel client—mobile, web ou desktop. + +## Résultat attendu + +Après avoir exécuté le `MdToPdfOneLiner` original, vous devriez voir un nouveau fichier `output.pdf` dans le dossier que vous avez indiqué. L’ouvrir affichera votre contenu Markdown rendu avec les titres, listes, blocs de code et images que vous avez inclus. Le PDF est entièrement recherchable et le texte peut être copié—contrairement aux PDF uniquement image. + +## Questions fréquentes + +**Q : Cette solution fonctionne‑t‑elle sur macOS/Linux ainsi que Windows ?** +R : Absolument. L’appel `Paths.get` abstrait les séparateurs spécifiques à chaque OS, et Aspose.HTML est multiplateforme. + +**Q : Puis‑je convertir d’autres langages de balisage (par ex. AsciiDoc) avec la même API ?** +R : La méthode `Converter.convert` prend en charge HTML, CSS et Markdown directement. Pour AsciiDoc, vous devez d’abord le transformer en HTML (par ex. avec AsciidoctorJ) puis fournir le HTML à Aspose. + +**Q : Existe‑t‑il une version gratuite d’Aspose.HTML ?** +R : Aspose propose une licence d’évaluation de 30 jours avec toutes les fonctionnalités. Pour la production, une licence commerciale est requise. + +## Conclusion – Vous avez maîtrisé la création de PDF à partir de Markdown en Java + +Nous vous avons guidé du problème initial—*comment créer un PDF à partir de markdown ?*—à une solution concise et exécutable, puis aux extensions réelles comme le traitement par lots et les services web. En exploitant la méthode `Converter.convert` d’Aspose.HTML, vous pouvez **convertir markdown en pdf** en quelques lignes de code, tout en conservant la flexibilité de personnaliser la taille de page, les en‑têtes, pieds de page et les paramètres de performance. + +Prochaines étapes ? Essayez de remplacer les `PdfSaveOptions` par une feuille de style personnalisée, expérimentez l’intégration de polices, ou intégrez la conversion dans votre pipeline CI afin que chaque README génère automatiquement un artefact PDF. Le ciel est la limite une fois que vous avez la base **java markdown to pdf** sous la main. + +Bon codage, et que vos PDF se rendent toujours exactement comme vous l’avez imaginé ! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/french/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/french/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..7eb72d5c5 --- /dev/null +++ b/html/french/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: Comment définir le DPI lors de la conversion d’une URL en PNG. Apprenez + à rendre du HTML en PNG, à définir la taille du viewport et à enregistrer du HTML + en PNG en utilisant Aspose.HTML en Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: fr +og_description: Comment définir le DPI lors de la conversion d’une URL en PNG. Guide + étape par étape pour rendre le HTML en PNG, contrôler la taille du viewport et enregistrer + le HTML en PNG avec Aspose.HTML. +og_title: Comment définir le DPI – Rendre le HTML en PNG avec AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: Comment définir le DPI – Rendre le HTML en PNG avec AsposeHTML +url: /fr/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# comment définir le DPI – Rendu HTML en PNG avec AsposeHTML + +Vous vous êtes déjà demandé **comment définir le DPI** pour une image de type capture d'écran générée à partir d'une page web ? Peut‑être avez‑vous besoin d'un PNG à 300 DPI pour l'impression, ou d'une vignette basse résolution pour une application mobile. Dans les deux cas, l'astuce consiste à indiquer au moteur de rendu le DPI logique souhaité, puis le laisser faire le travail lourd. + +Dans ce tutoriel, nous prendrons une URL en direct, la rendrons en fichier PNG, **définirons la taille du viewport**, ajusterons le DPI, et enfin **enregistrerons le HTML en PNG** — le tout avec Aspose.HTML pour Java. Aucun navigateur externe, aucun outil en ligne de commande encombrant — juste du code Java propre que vous pouvez intégrer à n'importe quel projet Maven ou Gradle. + +> **Astuce :** Si vous ne cherchez qu'une vignette rapide, vous pouvez garder le DPI à 96 DPI (la valeur par défaut pour la plupart des écrans). Pour des actifs prêts à l'impression, montez-le à 300 DPI ou plus. + +![exemple de comment définir le DPI](https://example.com/images/how-to-set-dpi.png "exemple de comment définir le DPI") + +## Ce dont vous avez besoin + +- **Java 17** (ou tout JDK récent). +- **Aspose.HTML for Java** 24.10 ou plus récent. Vous pouvez le récupérer depuis Maven Central : + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Une connexion Internet pour récupérer la page cible (l'exemple utilise `https://example.com/sample.html`). +- Permission d'écriture sur le dossier de sortie. + +C’est tout — pas de Selenium, pas de Chrome headless. Aspose.HTML effectue le rendu en‑processus, ce qui signifie que vous restez dans la JVM et évitez le surcoût du lancement d'un navigateur. + +## Étape 1 – Charger le document HTML depuis une URL + +Tout d'abord, nous créons une instance `HTMLDocument` pointant vers la page que nous voulons capturer. Le constructeur télécharge automatiquement le HTML, le parse, et prépare le DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Pourquoi c’est important :* En chargeant le document directement, vous évitez d'avoir besoin d'un client HTTP séparé. Aspose.HTML respecte les redirections, les cookies, et même l'authentification de base si vous intégrez les identifiants dans l'URL. + +## Étape 2 – Construire un sandbox avec le DPI et la taille de la fenêtre souhaités + +Un **sandbox** est la façon dont Aspose.HTML imite un environnement de navigateur. Ici, nous lui indiquons de se comporter comme un écran 1280 × 720 et, surtout, nous définissons le **device DPI**. Modifier le DPI change la densité de pixels de l'image rendue sans altérer la taille logique. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Pourquoi vous pourriez ajuster ces valeurs :* +- **Viewport size** contrôle le comportement des media queries CSS (`@media (max-width: …)`). +- **Device DPI** influence la taille physique de l'image lorsqu'elle est imprimée. Une image à 96 DPI convient aux écrans ; une image à 300 DPI conserve sa netteté sur papier. + +Si vous avez besoin d'une vignette carrée, changez simplement `setViewportSize(500, 500)` et gardez le DPI bas. + +## Étape 3 – Choisir PNG comme format de sortie + +Aspose.HTML prend en charge plusieurs formats raster (PNG, JPEG, BMP, GIF). PNG est sans perte, ce qui le rend parfait pour les captures d'écran où chaque pixel doit être préservé. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Vous pouvez également ajuster le niveau de compression (`pngOptions.setCompressionLevel(9)`) si la taille du fichier vous préoccupe. + +## Étape 4 – Rendre et enregistrer l'image + +Nous indiquons maintenant au document de **save** lui‑même sous forme d'image. La méthode `save` accepte un chemin de fichier et les options préalablement configurées. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Lorsque le programme se termine, vous trouverez un fichier PNG à `YOUR_DIRECTORY/sandboxed.png`. Ouvrez‑le — si vous avez défini le DPI à 300, les métadonnées de l'image le refléteront, même si les dimensions en pixels restent 1280 × 720. + +## Étape 5 – Vérifier le DPI (Optionnel mais pratique) + +Si vous voulez revérifier que le DPI a bien été appliqué, vous pouvez lire les métadonnées PNG avec une bibliothèque comme **metadata‑extractor** : + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Vous devriez voir `300` (ou la valeur que vous avez définie) affichée dans la console. Cette étape n’est pas requise pour le rendu, mais constitue une vérification rapide, surtout lorsque vous générez des actifs pour un flux de travail d’impression. + +## Questions fréquentes & cas particuliers + +### « Et si la page utilise JavaScript pour charger du contenu ? » + +Aspose.HTML exécute un **subset limité** de JavaScript. Pour la plupart des sites statiques, cela fonctionne immédiatement. Si la page dépend fortement de frameworks côté client (React, Angular, Vue), vous pourriez devoir pré‑rendre la page ou utiliser un navigateur headless à la place. Cependant, la définition du DPI fonctionne de la même façon une fois le DOM prêt. + +### « Puis‑je rendre un PDF au lieu d’un PNG ? » + +Absolument. Remplacez `ImageSaveOptions` par `PdfSaveOptions` et changez l’extension de sortie en `.pdf`. Le réglage du DPI influence toujours l’apparence rasterisée de toute image intégrée. + +### « Qu’en est‑il des captures d’écran haute résolution pour les écrans Retina ? » + +Il suffit de doubler les dimensions du viewport tout en conservant le DPI à 96 DPI, ou de garder le même viewport et d’augmenter le DPI à 192. Le PNG résultant contiendra deux fois plus de pixels, vous offrant cet aspect net propre aux écrans Retina. + +### « Dois‑je nettoyer les ressources ? » + +`HTMLDocument` implémente `AutoCloseable`. Dans une application de production, encapsulez‑le dans un bloc try‑with‑resources : + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Cela garantit que les ressources natives sont libérées rapidement. + +## Exemple complet fonctionnel (prêt à copier‑coller) + +Voici le programme complet, prêt à être exécuté. Remplacez `YOUR_DIRECTORY` par un dossier réel sur votre machine. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Exécutez la classe, et vous obtiendrez un PNG qui respecte le paramètre **comment définir le DPI** que vous avez spécifié. + +## Conclusion + +Nous avons parcouru **comment définir le DPI** lors du **rendu HTML en PNG**, couvert l’étape **définir la taille du viewport**, et montré comment **enregistrer le HTML en PNG** en utilisant Aspose.HTML pour Java. Les points clés sont : + +- Utilisez un **sandbox** pour contrôler le DPI et le viewport. +- Choisissez les bons **ImageSaveOptions** pour une sortie sans perte. +- Vérifiez les métadonnées DPI si vous devez garantir la qualité d’impression. + +À partir d’ici, vous pouvez expérimenter avec différentes valeurs de DPI, des viewports plus grands, ou même traiter un lot d’URL. Vous voulez convertir tout un site web en vignettes PNG ? Il suffit de boucler sur un tableau d’URL et de réutiliser la même configuration de sandbox. + +Bon rendu, et que vos captures d’écran soient toujours pixel‑perfect ! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/french/java/css-html-form-editing/_index.md b/html/french/java/css-html-form-editing/_index.md index d508a3b7f..ad96bc600 100644 --- a/html/french/java/css-html-form-editing/_index.md +++ b/html/french/java/css-html-form-editing/_index.md @@ -30,9 +30,11 @@ Passons maintenant à la vitesse supérieure et découvrons comment modifier et Découvrez comment utiliser Aspose.HTML pour Java pour appliquer des techniques CSS avancées, notamment des marges de page personnalisées et du contenu dynamique. Un didacticiel pratique et détaillé pour les développeurs. ### [Édition et soumission de formulaires HTML avec Aspose.HTML pour Java](./html-form-editing/) Découvrez comment modifier et soumettre des formulaires HTML par programmation à l'aide d'Aspose.HTML pour Java dans ce guide complet étape par étape. +### [Comment récupérer le style en Java – charger le HTML et utiliser le sélecteur de requête](./how-to-get-style-in-java-load-html-query-selector/) +Apprenez à charger un document HTML en Java avec Aspose.HTML et à extraire les styles via un sélecteur CSS. {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/french/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/french/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..672cda554 --- /dev/null +++ b/html/french/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,188 @@ +--- +category: general +date: 2026-01-14 +description: Comment obtenir le style en Java – apprenez comment charger un document + HTML, utilisez un exemple de sélecteur de requête, et lisez la propriété background-color + avec Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: fr +og_description: Comment obtenir le style en Java – guide étape par étape pour charger + un document HTML, exécuter un exemple de sélecteur de requête et récupérer la propriété + background-color. +og_title: Comment récupérer le style en Java – charger le HTML et le sélecteur de + requête +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: Comment obtenir le style en Java – charger le HTML et le sélecteur de requête +url: /fr/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# comment obtenir le style en Java – charger du HTML & query selector + +Vous vous êtes déjà demandé **comment obtenir le style** d’un élément lorsque vous analysez du HTML avec Java ? Peut‑être que vous créez un scraper, un outil de test, ou que vous devez simplement vérifier des indices visuels dans une page générée. Bonne nouvelle : Aspose.HTML rend cela très simple. Dans ce tutoriel, nous allons charger un document HTML, utiliser un **exemple de query selector**, puis lire la **propriété background-color** d’un élément `
`. Pas de magie, juste du code Java clair que vous pouvez copier‑coller et exécuter. + +## Ce dont vous avez besoin + +Avant de commencer, assurez‑vous d’avoir : + +* **Java 17** (ou tout JDK récent) – l’API fonctionne avec Java 8+ mais les versions plus récentes offrent de meilleures performances. +* **Aspose.HTML for Java** – vous pouvez l’obtenir depuis Maven Central (`com.aspose:aspose-html:23.10` à la date de rédaction). +* Un petit fichier HTML (`input.html`) contenant au moins un `
` avec une couleur d’arrière‑plan définie en ligne ou via une feuille de style. + +C’est tout. Aucun framework supplémentaire, aucun navigateur lourd, juste du Java pur et Aspose.HTML. + +## Étape 1 : Charger le document HTML + +La première chose à faire est de **charger le document HTML** en mémoire. La classe `HTMLDocument` d’Aspose.HTML abstrait la gestion du système de fichiers et vous fournit un DOM que vous pouvez interroger. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Pourquoi c’est important :** Charger le document crée un arbre DOM analysé, qui constitue la base de toute évaluation CSS ou JavaScript ultérieure. Si le fichier est introuvable, Aspose lève une `FileNotFoundException` descriptive, alors vérifiez bien le chemin. + +### Astuce pro +Si vous récupérez le HTML depuis une URL au lieu d’un fichier, passez simplement la chaîne d’URL au constructeur – Aspose gère la requête HTTP pour vous. + +## Étape 2 : Utiliser un exemple de query selector + +Maintenant que le document est en mémoire, utilisons un **exemple de query selector** pour récupérer le premier élément `
`. La méthode `querySelector` reprend la syntaxe des sélecteurs CSS que vous connaissez déjà depuis le navigateur. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Pourquoi c’est important :** `querySelector` renvoie le premier nœud correspondant, ce qui est parfait quand vous avez besoin du style d’un seul élément. Si vous avez besoin de plusieurs éléments, `querySelectorAll` renvoie un `NodeList`. + +### Cas limite +Si le sélecteur ne correspond à rien, `divElement` sera `null`. Protégez toujours votre code avant de lire les styles : + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Étape 3 : Obtenir le style calculé + +Avec l’élément en main, l’étape suivante consiste à **analyser le HTML en Java** suffisamment pour calculer les valeurs CSS finales. Aspose.HTML fait le gros du travail : il résout la cascade, l’héritage et même les feuilles de style externes. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Pourquoi c’est important :** Le style calculé reflète les valeurs exactes que le navigateur appliquerait après le traitement de toutes les règles CSS. C’est plus fiable que de lire l’attribut `style` brut, qui peut être incomplet. + +## Étape 4 : Récupérer la propriété background‑color + +Enfin, nous extrayons la **propriété background-color** qui nous intéresse. La méthode `getPropertyValue` renvoie la valeur sous forme de chaîne (par ex., `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Ce que vous verrez :** Si votre `
` possède `background-color: #ff5733;` en ligne ou via une feuille de style, la console affichera quelque chose comme `Computed background‑color: rgb(255, 87, 51)`. + +### Piège fréquent +Lorsque la propriété n’est pas définie, `getPropertyValue` renvoie une chaîne vide. C’est le signal pour revenir à une valeur par défaut ou inspecter les styles du parent. + +## Exemple complet fonctionnel + +Voici le programme complet, prêt à être exécuté : + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Sortie attendue (exemple) :** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Si le `
` n’a aucune couleur d’arrière‑plan définie, la sortie sera une ligne vide – c’est votre indication d’examiner les styles hérités. + +## Astuces, trucs et points d’attention + +| Situation | Que faire | +|-----------|-----------| +| **Plusieurs éléments `
`** | Utilisez `querySelectorAll("div")` et itérez sur le `NodeList`. | +| **Fichiers CSS externes** | Assurez‑vous que le fichier HTML les référence avec les bons chemins ; Aspose.HTML les récupérera automatiquement. | +| **Attribut `style` en ligne uniquement** | `getComputedStyle` fonctionne toujours – il fusionne les styles en ligne avec les valeurs par défaut. | +| **Problèmes de performance** | Chargez le document une seule fois, réutilisez l’objet `HTMLDocument` si vous devez interroger de nombreux éléments. | +| **Exécution sur Android** | Aspose.HTML for Java supporte Android, mais vous devez inclure l’AAR spécifique à Android. | + +## Sujets liés que vous pourriez explorer + +* **Parsing HTML avec Jsoup vs. Aspose.HTML** – quand choisir l’un ou l’autre. +* **Exporter les styles calculés en JSON** – utile pour les front‑ends pilotés par API. +* **Automatiser la génération de captures d’écran** – combinez les styles calculés avec Aspose.PDF pour des tests de régression visuelle. + +--- + +### Conclusion + +Vous savez maintenant **comment obtenir le style** de n’importe quel élément lorsque vous **chargez le document HTML** avec Aspose.HTML, exécutez un **exemple de query selector**, et extrayez la **propriété background‑color**. Le code est autonome, fonctionne avec n’importe quel JDK récent, et gère proprement les éléments manquants ou les styles non définis. Vous pouvez étendre cette approche pour récupérer les tailles de police, les marges, ou même les valeurs calculées après l’exécution de JavaScript (Aspose.HTML supporte également l’évaluation de scripts). + +Essayez‑le, modifiez le sélecteur, et découvrez quels autres trésors CSS vous pouvez révéler. Bon codage ! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/german/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/german/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..7e0840aa0 --- /dev/null +++ b/html/german/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: Wie man DPI beim Konvertieren einer URL zu PNG einstellt. Lernen Sie, + HTML zu PNG zu rendern, die Viewport-Größe festzulegen und HTML mit Aspose.HTML + in Java als PNG zu speichern. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: de +og_description: Wie man DPI beim Konvertieren einer URL zu PNG festlegt. Schritt‑für‑Schritt‑Anleitung + zum Rendern von HTML zu PNG, zur Steuerung der Viewport‑Größe und zum Speichern + von HTML als PNG mit Aspose.HTML. +og_title: Wie man DPI einstellt – HTML zu PNG rendern mit AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: Wie man DPI einstellt – HTML zu PNG rendern mit AsposeHTML +url: /de/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Wie man DPI festlegt – HTML zu PNG rendern mit AsposeHTML + +Haben Sie sich jemals gefragt, **wie man DPI** für ein screenshot‑ähnliches Bild, das aus einer Webseite erzeugt wird, festlegt? Vielleicht benötigen Sie ein 300 DPI PNG für den Druck oder ein niedrigauflösendes Thumbnail für eine mobile App. In beiden Fällen besteht der Trick darin, der Rendering‑Engine das gewünschte logische DPI mitzuteilen und sie dann die schwere Arbeit erledigen zu lassen. + +In diesem Tutorial nehmen wir eine Live‑URL, rendern sie zu einer PNG‑Datei, **setzen die Viewport‑Größe**, passen das DPI an und speichern schließlich **HTML als PNG** – alles mit Aspose.HTML für Java. Keine externen Browser, keine unübersichtlichen Befehlszeilentools – nur sauberer Java‑Code, den Sie in jedes Maven‑ oder Gradle‑Projekt einbinden können. + +> **Pro‑Tipp:** Wenn Sie nur ein schnelles Thumbnail benötigen, können Sie das DPI bei 96 DPI belassen (der Standard für die meisten Bildschirme). Für druckfertige Assets erhöhen Sie es auf 300 DPI oder mehr. + +![Beispiel für DPI-Einstellung](https://example.com/images/how-to-set-dpi.png "Beispiel für DPI-Einstellung") + +## Was Sie benötigen + +- **Java 17** (oder ein aktuelles JDK). +- **Aspose.HTML for Java** 24.10 oder neuer. Sie können es von Maven Central beziehen: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Eine Internetverbindung, um die Zielseite abzurufen (das Beispiel verwendet `https://example.com/sample.html`). +- Schreibberechtigung für den Ausgabepfad. + +Das war's – kein Selenium, kein Headless‑Chrome. Aspose.HTML führt das Rendering im Prozess aus, was bedeutet, dass Sie innerhalb der JVM bleiben und den Aufwand für das Starten eines Browsers vermeiden. + +## Schritt 1 – HTML‑Dokument von einer URL laden + +Zuerst erstellen wir eine `HTMLDocument`‑Instanz, die auf die Seite zeigt, die wir erfassen möchten. Der Konstruktor lädt das HTML automatisch herunter, parsed es und bereitet das DOM vor. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Warum das wichtig ist:* Durch das direkte Laden des Dokuments entfallen separate HTTP‑Clients. Aspose.HTML berücksichtigt Weiterleitungen, Cookies und sogar die Basisauthentifizierung, wenn Sie Anmeldeinformationen in die URL einbetten. + +## Schritt 2 – Sandbox mit gewünschtem DPI und Viewport erstellen + +Eine **Sandbox** ist Aspose.HTMLs Methode, eine Browser‑Umgebung zu simulieren. Hier lassen wir sie so tun, als wäre sie ein 1280 × 720‑Bildschirm und setzen dabei entscheidend das **Device‑DPI**. Das Ändern des DPI verändert die Pixeldichte des gerenderten Bildes, ohne die logische Größe zu ändern. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Warum Sie diese Werte anpassen könnten:* +- **Viewport‑Größe** steuert, wie CSS‑Media‑Queries (`@media (max-width: …)`) reagieren. +- **Device‑DPI** beeinflusst die physische Größe des Bildes beim Druck. Ein 96 DPI‑Bild sieht auf Bildschirmen gut aus; ein 300 DPI‑Bild behält die Schärfe auf Papier bei. + +Wenn Sie ein quadratisches Thumbnail benötigen, ändern Sie einfach `setViewportSize(500, 500)` und lassen das DPI niedrig. + +## Schritt 3 – PNG als Ausgabeformat wählen + +Aspose.HTML unterstützt mehrere Rasterformate (PNG, JPEG, BMP, GIF). PNG ist verlustfrei, was es ideal für Screenshots macht, bei denen jeder Pixel erhalten bleiben soll. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Sie können außerdem die Kompressionsstufe anpassen (`pngOptions.setCompressionLevel(9)`), falls Sie sich um die Dateigröße sorgen. + +## Schritt 4 – Bild rendern und speichern + +Jetzt lassen wir das Dokument **sich selbst** als Bild **speichern**. Die `save`‑Methode erwartet einen Dateipfad und die zuvor konfigurierten Optionen. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Wenn das Programm beendet ist, finden Sie eine PNG‑Datei unter `YOUR_DIRECTORY/sandboxed.png`. Öffnen Sie sie – wenn Sie das DPI auf 300 gesetzt haben, wird das Bild‑Metadaten‑Tag dies widerspiegeln, obwohl die Pixelabmessungen weiterhin 1280 × 720 betragen. + +## Schritt 5 – DPI überprüfen (optional, aber praktisch) + +Wenn Sie sicherstellen möchten, dass das DPI wirklich angewendet wurde, können Sie die PNG‑Metadaten mit einer leichten Bibliothek wie **metadata‑extractor** auslesen: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Sie sollten `300` (oder den von Ihnen gesetzten Wert) in der Konsole ausgegeben sehen. Dieser Schritt ist für das Rendering nicht erforderlich, aber er dient als schneller Plausibilitätstest, besonders wenn Sie Assets für einen Druck‑Workflow erzeugen. + +## Häufige Fragen & Sonderfälle + +### „Was ist, wenn die Seite JavaScript verwendet, um Inhalte zu laden?“ + +Aspose.HTML führt einen **eingeschränkten Teil** von JavaScript aus. Für die meisten statischen Seiten funktioniert es sofort. Wenn die Seite stark von clientseitigen Frameworks (React, Angular, Vue) abhängt, müssen Sie die Seite eventuell vor‑rendern oder stattdessen einen Headless‑Browser verwenden. Das Setzen des DPI funktioniert jedoch genauso, sobald das DOM bereit ist. + +### „Kann ich ein PDF statt PNG rendern?“ + +Natürlich. Ersetzen Sie `ImageSaveOptions` durch `PdfSaveOptions` und ändern Sie die Ausgabedateierweiterung zu `.pdf`. Die DPI‑Einstellung beeinflusst weiterhin das gerasterte Erscheinungsbild eingebetteter Bilder. + +### „Wie sieht es mit hochauflösenden Screenshots für Retina‑Displays aus?“ + +Verdoppeln Sie einfach die Viewport‑Abmessungen bei gleichbleibendem DPI von 96 DPI, oder behalten Sie den Viewport bei und erhöhen das DPI auf 192. Das resultierende PNG enthält dann doppelt so viele Pixel und liefert das scharfe Retina‑Gefühl. + +### „Muss ich Ressourcen aufräumen?“ + +`HTMLDocument` implementiert `AutoCloseable`. In einer Produktions‑App sollten Sie es in einem try‑with‑resources‑Block einbetten: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Damit werden native Ressourcen umgehend freigegeben. + +## Vollständiges funktionierendes Beispiel (Copy‑Paste‑bereit) + +Unten finden Sie das komplette, sofort ausführbare Programm. Ersetzen Sie `YOUR_DIRECTORY` durch einen tatsächlichen Ordner auf Ihrem Rechner. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Führen Sie die Klasse aus, und Sie erhalten ein PNG, das die von Ihnen festgelegte **DPI‑Einstellung** berücksichtigt. + +## Fazit + +Wir haben gezeigt, **wie man DPI festlegt**, wenn Sie **HTML zu PNG rendern**, den Schritt **Viewport‑Größe setzen** behandelt und Ihnen gezeigt, wie Sie **HTML als PNG speichern** mit Aspose.HTML für Java. Die wichtigsten Erkenntnisse sind: + +- Verwenden Sie eine **Sandbox**, um DPI und Viewport zu steuern. +- Wählen Sie die passenden **ImageSaveOptions** für verlustfreie Ausgabe. +- Überprüfen Sie die DPI‑Metadaten, wenn Sie Druckqualität garantieren müssen. + +Ab hier können Sie mit verschiedenen DPI‑Werten, größeren Viewports oder sogar einer Batch‑Verarbeitung einer URL‑Liste experimentieren. Möchten Sie eine komplette Website in PNG‑Thumbnails umwandeln? Durchlaufen Sie einfach ein Array von URLs und verwenden Sie dieselbe Sandbox‑Konfiguration erneut. + +Viel Spaß beim Rendern, und möge Ihr Screenshot immer pixel‑perfekt sein! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/german/java/css-html-form-editing/_index.md b/html/german/java/css-html-form-editing/_index.md index 6a67a40d1..c788d06f7 100644 --- a/html/german/java/css-html-form-editing/_index.md +++ b/html/german/java/css-html-form-editing/_index.md @@ -30,9 +30,11 @@ Lassen Sie uns nun einen Gang höher schalten und untersuchen, wie Sie HTML-Form Erfahren Sie, wie Sie mit Aspose.HTML für Java erweiterte CSS-Techniken anwenden, darunter benutzerdefinierte Seitenränder und dynamische Inhalte. Ein ausführliches, praktisches Tutorial für Entwickler. ### [Bearbeiten und Senden von HTML-Formularen mit Aspose.HTML für Java](./html-form-editing/) Erfahren Sie in dieser umfassenden Schritt-für-Schritt-Anleitung, wie Sie mit Aspose.HTML für Java programmgesteuert HTML-Formulare bearbeiten und übermitteln. +### [Wie man Stil in Java abruft – HTML laden & Query Selector](./how-to-get-style-in-java-load-html-query-selector/) +Erfahren Sie, wie Sie mit Aspose.HTML für Java CSS-Stile aus einer HTML-Datei laden und über Query Selector abrufen. {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/german/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/german/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..5367c5ab4 --- /dev/null +++ b/html/german/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,186 @@ +--- +category: general +date: 2026-01-14 +description: Wie man Stil in Java abruft – lernen Sie, wie man ein HTML‑Dokument lädt, + ein Query‑Selector‑Beispiel verwendet und die Hintergrundfarbe‑Eigenschaft mit Aspose.HTML + ausliest. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: de +og_description: Wie man Stil in Java erhält – Schritt‑für‑Schritt‑Anleitung zum Laden + eines HTML‑Dokuments, Ausführen eines Query‑Selector‑Beispiels und Abrufen der background-color‑Eigenschaft. +og_title: Wie man Stil in Java bekommt – HTML laden & Query-Selektor +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: Wie man Stil in Java bekommt – HTML laden & Query-Selektor +url: /de/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Wie man Stil in Java abruft – HTML laden & Query Selector verwenden + +Haben Sie sich jemals gefragt, **wie man den Stil** eines Elements ermittelt, wenn Sie HTML mit Java parsen? Vielleicht bauen Sie einen Scraper, ein Test‑Tool oder müssen einfach visuelle Hinweise auf einer erzeugten Seite prüfen. Die gute Nachricht: Aspose.HTML macht das kinderleicht. In diesem Tutorial zeigen wir, wie man ein HTML‑Dokument lädt, ein **Query‑Selector‑Beispiel** verwendet und schließlich die **background‑color‑Eigenschaft** eines `
`‑Elements ausliest. Kein Hexenwerk, nur klarer Java‑Code, den Sie kopieren, einfügen und ausführen können. + +## Was Sie benötigen + +Bevor wir starten, stellen Sie sicher, dass Sie folgendes haben: + +* **Java 17** (oder ein aktuelles JDK) – die API funktioniert ab Java 8, aber neuere Versionen bieten bessere Performance. +* **Aspose.HTML for Java**‑Bibliothek – Sie können sie von Maven Central beziehen (`com.aspose:aspose-html:23.10` zum Zeitpunkt dieses Schreibens). +* Eine kleine HTML‑Datei (`input.html`), die mindestens ein `
` mit einem CSS‑background‑color‑Wert enthält, entweder inline oder über ein Stylesheet. + +Das war’s. Keine zusätzlichen Frameworks, keine schweren Browser – nur reines Java und Aspose.HTML. + +## Schritt 1: Das HTML‑Dokument laden + +Das Erste, was Sie tun müssen, ist das **HTML‑Dokument laden** und im Speicher halten. Die Klasse `HTMLDocument` von Aspose.HTML übernimmt die Dateisystem‑Abwicklung und liefert Ihnen ein DOM, das Sie abfragen können. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Warum das wichtig ist:** Das Laden des Dokuments erzeugt einen geparsten DOM‑Baum, der die Basis für jede nachfolgende CSS‑ oder JavaScript‑Auswertung bildet. Wenn die Datei nicht gefunden wird, wirft Aspose eine aussagekräftige `FileNotFoundException`, also prüfen Sie den Pfad doppelt. + +### Profi‑Tipp +Wenn Sie HTML von einer URL statt von einer Datei laden, übergeben Sie einfach den URL‑String an den Konstruktor – Aspose erledigt die HTTP‑Anfrage für Sie. + +## Schritt 2: Ein Query‑Selector‑Beispiel verwenden + +Jetzt, wo das Dokument im Speicher ist, **query selector example** wir, um das erste `
`‑Element zu holen. Die Methode `querySelector` verwendet dieselbe CSS‑Selektor‑Syntax, die Sie bereits aus dem Browser kennen. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Warum das wichtig ist:** `querySelector` gibt das erste passende Node zurück, was ideal ist, wenn Sie nur den Stil eines einzelnen Elements benötigen. Für mehrere Elemente liefert `querySelectorAll` eine `NodeList`. + +### Sonderfall +Falls der Selektor nichts findet, ist `divElement` `null`. Schützen Sie sich immer davor, bevor Sie versuchen, Stile auszulesen: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Schritt 3: Den berechneten Stil erhalten + +Mit dem Element in der Hand ist der nächste Schritt, **parse html java** genug zu sein, um die endgültigen CSS‑Werte zu berechnen. Aspose.HTML übernimmt die schwere Arbeit: Es löst Kaskade, Vererbung und sogar externe Stylesheets auf. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Warum das wichtig ist:** Der berechnete Stil spiegelt exakt die Werte wider, die ein Browser nach Verarbeitung aller CSS‑Regeln anwenden würde. Er ist zuverlässiger als das reine Auslesen des `style`‑Attributs, das unvollständig sein kann. + +## Schritt 4: Die background‑color‑Eigenschaft auslesen + +Zum Schluss holen wir die **background‑color‑Eigenschaft**, die uns interessiert. Die Methode `getPropertyValue` gibt den Wert als String zurück (z. B. `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Was Sie sehen werden:** Wenn Ihr `
` `background-color: #ff5733;` entweder inline oder über ein Stylesheet definiert hat, gibt die Konsole etwa `Computed background‑color: rgb(255, 87, 51)` aus. + +### Häufiges Stolper‑Problem +Wenn die Eigenschaft nicht definiert ist, liefert `getPropertyValue` einen leeren String. Das ist ein Hinweis, entweder einen Standardwert zu verwenden oder die Stile des Elternelements zu prüfen. + +## Vollständiges funktionierendes Beispiel + +Alles zusammengeführt, hier das komplette, sofort ausführbare Programm: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Erwartete Ausgabe (Beispiel):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Hat das `
` keine Hintergrundfarbe, wird eine leere Zeile ausgegeben – das ist Ihr Signal, sich die vererbten Stile anzusehen. + +## Tipps, Tricks und Dinge, auf die Sie achten sollten + +| Situation | Was zu tun ist | +|-----------|----------------| +| **Mehrere `
`‑Elemente** | Verwenden Sie `querySelectorAll("div")` und iterieren Sie über die `NodeList`. | +| **Externe CSS‑Dateien** | Stellen Sie sicher, dass die HTML‑Datei sie mit korrekten Pfaden referenziert; Aspose.HTML holt sie automatisch. | +| **Nur Inline‑`style`‑Attribut** | `getComputedStyle` funktioniert weiterhin – es kombiniert Inline‑Stile mit Standardwerten. | +| **Performance‑Bedenken** | Laden Sie das Dokument einmal und wiederverwenden Sie das `HTMLDocument`‑Objekt, wenn Sie viele Elemente abfragen. | +| **Ausführung auf Android** | Aspose.HTML for Java unterstützt Android, Sie müssen jedoch das Android‑spezifische AAR einbinden. | + +## Verwandte Themen, die Sie erkunden könnten + +* **HTML‑Parsing mit Jsoup vs. Aspose.HTML** – wann welches Tool sinnvoll ist. +* **Export berechneter Stile nach JSON** – nützlich für API‑gesteuerte Front‑Ends. +* **Automatisierte Screenshot‑Erstellung** – kombinieren Sie berechnete Stile mit Aspose.PDF für visuelle Regressionstests. + +--- + +### Fazit + +Sie wissen jetzt, **wie man Stil** eines beliebigen Elements ermittelt, wenn Sie ein **HTML‑Dokument laden** mit Aspose.HTML, ein **query selector example** ausführen und die **background‑color‑Eigenschaft** extrahieren. Der Code ist eigenständig, läuft auf jedem aktuellen JDK und behandelt fehlende Elemente oder undefinierte Stile elegant. Von hier aus können Sie das Vorgehen erweitern, um Schriftgrößen, Abstände oder sogar berechnete Werte nach JavaScript‑Ausführung zu holen (Aspose.HTML unterstützt ebenfalls Skriptauswertung). + +Probieren Sie es aus, passen Sie den Selektor an und entdecken Sie weitere CSS‑Schätze. Viel Spaß beim Coden! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/greek/java/conversion-html-to-various-image-formats/_index.md b/html/greek/java/conversion-html-to-various-image-formats/_index.md index 4948c7833..247661f48 100644 --- a/html/greek/java/conversion-html-to-various-image-formats/_index.md +++ b/html/greek/java/conversion-html-to-various-image-formats/_index.md @@ -98,6 +98,7 @@ weight: 24 Μάθετε πώς να μετατρέπετε HTML σε εικόνες PNG σε Java με το Aspose.HTML. Ένας ολοκληρωμένος οδηγός με οδηγίες βήμα‑βήμα. ### [Μετατροπή HTML σε TIFF](./convert-html-to-tiff/) Μάθετε πώς να μετατρέπετε εύκολα HTML σε TIFF χρησιμοποιώντας το Aspose.HTML για Java. Οδηγός βήμα‑βήμα για αποτελεσματική διαχείριση εγγράφων. +### [Πώς να ορίσετε DPI – Απόδοση HTML σε PNG με AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) ## Συχνές Ερωτήσεις diff --git a/html/greek/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/greek/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..834ecb46a --- /dev/null +++ b/html/greek/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: πώς να ορίσετε dpi κατά τη μετατροπή ενός URL σε PNG. Μάθετε πώς να αποδίδετε + HTML σε PNG, να ορίζετε το μέγεθος του viewport και να αποθηκεύετε HTML ως PNG χρησιμοποιώντας + το Aspose.HTML σε Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: el +og_description: πώς να ορίσετε dpi κατά τη μετατροπή ενός URL σε PNG. Οδηγός βήμα‑προς‑βήμα + για την απόδοση HTML σε PNG, τον έλεγχο του μεγέθους του viewport και την αποθήκευση + του HTML ως PNG χρησιμοποιώντας το Aspose.HTML. +og_title: πώς να ορίσετε dpi – Απόδοση HTML σε PNG με το AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: πώς να ορίσετε dpi – Απόδοση HTML σε PNG με το AsposeHTML +url: /el/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# πώς να ορίσετε dpi – Απόδοση HTML σε PNG με AsposeHTML + +Έχετε αναρωτηθεί ποτέ **πώς να ορίσετε dpi** για μια εικόνα τύπου screenshot που δημιουργείται από μια ιστοσελίδα; Ίσως χρειάζεστε ένα PNG 300 DPI για εκτύπωση, ή μια μικρή μικρογραφία χαμηλής ανάλυσης για μια εφαρμογή κινητού. Σε κάθε περίπτωση, το κόλπο είναι να πείτε στη μηχανή απόδοσης ποιο λογικό DPI θέλετε, και στη συνέχεια να αφήσετε αυτήν να κάνει τη βαριά δουλειά. + +Σε αυτό το tutorial θα πάρουμε ένα ζωντανό URL, θα το αποδώσουμε σε αρχείο PNG, **ορίσουμε το μέγεθος του viewport**, θα προσαρμόσουμε το DPI, και τελικά **αποθηκεύσουμε το HTML ως PNG**—όλα με το Aspose.HTML για Java. Χωρίς εξωτερικά προγράμματα περιήγησης, χωρίς ακατάστατα εργαλεία γραμμής εντολών—απλώς καθαρός κώδικας Java που μπορείτε να ενσωματώσετε σε οποιοδήποτε έργο Maven ή Gradle. + +> **Συμβουλή επαγγελματία:** Αν θέλετε μόνο μια γρήγορη μικρογραφία, μπορείτε να διατηρήσετε το DPI στα 96 DPI (η προεπιλογή για τις περισσότερες οθόνες). Για περιουσιακά στοιχεία έτοιμα για εκτύπωση, αυξήστε το σε 300 DPI ή περισσότερο. + +![παράδειγμα ορισμού dpi](https://example.com/images/how-to-set-dpi.png "παράδειγμα ορισμού dpi") + +## Τι Θα Χρειαστείτε + +- **Java 17** (ή οποιοδήποτε πρόσφατο JDK). +- **Aspose.HTML for Java** 24.10 ή νεότερη. Μπορείτε να την κατεβάσετε από το Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Σύνδεση στο διαδίκτυο για λήψη της σελίδας-στόχου (το παράδειγμα χρησιμοποιεί `https://example.com/sample.html`). +- Δικαίωμα εγγραφής στο φάκελο εξόδου. + +Αυτό είναι όλο—χωρίς Selenium, χωρίς headless Chrome. Το Aspose.HTML κάνει την απόδοση εντός της διαδικασίας, πράγμα που σημαίνει ότι παραμένετε μέσα στη JVM και αποφεύγετε το κόστος εκκίνησης ενός προγράμματος περιήγησης. + +## Βήμα 1 – Φόρτωση του HTML Εγγράφου από URL + +Αρχικά δημιουργούμε μια παρουσία `HTMLDocument` που δείχνει στη σελίδα που θέλουμε να καταγράψουμε. Ο κατασκευαστής κατεβάζει αυτόματα το HTML, το αναλύει και προετοιμάζει το DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Γιατί είναι σημαντικό:* Φορτώνοντας το έγγραφο απευθείας, παρακάμπτετε την ανάγκη για ξεχωριστό HTTP client. Το Aspose.HTML σέβεται τις ανακατευθύνσεις, τα cookies, και ακόμη και την βασική πιστοποίηση αν ενσωματώσετε διαπιστευτήρια στο URL. + +## Βήμα 2 – Δημιουργία Sandbox με το Επιθυμητό DPI και Viewport + +Ένα **sandbox** είναι ο τρόπος του Aspose.HTML να μιμηθεί ένα περιβάλλον προγράμματος περιήγησης. Εδώ του λέμε να προσποιηθεί ότι είναι μια οθόνη 1280 × 720 και, κρίσιμα, ορίζουμε το **device DPI**. Η αλλαγή του DPI αλλάζει την πυκνότητα εικονοστοιχείων της αποδοθείσας εικόνας χωρίς να τροποποιεί το λογικό μέγεθος. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Γιατί μπορεί να θέλετε να προσαρμόσετε αυτές τις τιμές:* +- **Το μέγεθος του viewport** ελέγχει τη συμπεριφορά των CSS media queries (`@media (max-width: …)`). +- **Το Device DPI** επηρεάζει το φυσικό μέγεθος της εικόνας όταν εκτυπώνεται. Μια εικόνα 96 DPI φαίνεται καλά στις οθόνες· μια εικόνα 300 DPI διατηρεί την ευκρίνεια στο χαρτί. + +Αν χρειάζεστε μια τετράγωνη μικρογραφία, απλώς αλλάξτε `setViewportSize(500, 500)` και διατηρήστε το DPI χαμηλό. + +## Βήμα 3 – Επιλογή PNG ως Μορφή Εξόδου + +Το Aspose.HTML υποστηρίζει διάφορες μορφές raster (PNG, JPEG, BMP, GIF). Το PNG είναι loss‑less, κάτι που το καθιστά ιδανικό για screenshots όπου θέλετε κάθε εικονοστοιχείο να διατηρείται. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Μπορείτε επίσης να ρυθμίσετε το επίπεδο συμπίεσης (`pngOptions.setCompressionLevel(9)`) αν σας ανησυχεί το μέγεθος του αρχείου. + +## Βήμα 4 – Απόδοση και Αποθήκευση της Εικόνας + +Τώρα λέμε στο έγγραφο να **αποθηκεύσει** τον εαυτό του ως εικόνα. Η μέθοδος `save` δέχεται μια διαδρομή αρχείου και τις προηγουμένως ρυθμισμένες επιλογές. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Όταν το πρόγραμμα ολοκληρωθεί, θα βρείτε ένα αρχείο PNG στο `YOUR_DIRECTORY/sandboxed.png`. Ανοίξτε το—αν έχετε ορίσει το DPI σε 300, τα μεταδεδομένα της εικόνας θα το αντικατοπτρίζουν, παρόλο που οι διαστάσεις των εικονοστοιχείων παραμένουν 1280 × 720. + +## Βήμα 5 – Επαλήθευση του DPI (Προαιρετικό αλλά Χρήσιμο) + +Αν θέλετε να ελέγξετε ξανά ότι το DPI εφαρμόστηκε πραγματικά, μπορείτε να διαβάσετε τα μεταδεδομένα PNG με μια ελαφριά βιβλιοθήκη όπως η **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Θα πρέπει να δείτε `300` (ή ό,τι έχετε ορίσει) να εκτυπώνεται στην κονσόλα. Αυτό το βήμα δεν απαιτείται για την απόδοση, αλλά είναι ένας γρήγορος έλεγχος λογικής, ειδικά όταν δημιουργείτε περιουσιακά στοιχεία για διαδικασία εκτύπωσης. + +## Συχνές Ερωτήσεις & Ακραίες Περιπτώσεις + +### “Τι γίνεται αν η σελίδα χρησιμοποιεί JavaScript για φόρτωση περιεχομένου;” + +Το Aspose.HTML εκτελεί ένα **περιορισμένο υποσύνολο** του JavaScript. Για τις περισσότερες στατικές ιστοσελίδες λειτουργεί αμέσως. Αν η σελίδα εξαρτάται έντονα από client‑side frameworks (React, Angular, Vue), ίσως χρειαστεί να προ‑αποδώσετε τη σελίδα ή να χρησιμοποιήσετε ένα headless browser. Ωστόσο, η ρύθμιση DPI λειτουργεί με τον ίδιο τρόπο μόλις το DOM είναι έτοιμο. + +### “Μπορώ να αποδώσω PDF αντί για PNG;” + +Απόλυτα. Αντικαταστήστε το `ImageSaveOptions` με `PdfSaveOptions` και αλλάξτε την επέκταση εξόδου σε `.pdf`. Η ρύθμιση DPI εξακολουθεί να επηρεάζει την rasterized εμφάνιση τυχόν ενσωματωμένων εικόνων. + +### “Τι γίνεται με τα υψηλής ανάλυσης screenshots για οθόνες retina;” + +Απλώς διπλασιάστε τις διαστάσεις του viewport διατηρώντας το DPI στα 96 DPI, ή διατηρήστε το viewport και αυξήστε το DPI σε 192. Το παραγόμενο PNG θα περιέχει δύο φορές περισσότερα εικονοστοιχεία, προσφέροντας αυτή τη διακριτική αίσθηση retina. + +### “Χρειάζεται να καθαρίσω πόρους;” + +`HTMLDocument` υλοποιεί το `AutoCloseable`. Σε μια παραγωγική εφαρμογή, τυλίξτε το σε ένα μπλοκ try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## Πλήρες Παράδειγμα Εργασίας (Έτοιμο για Αντιγραφή‑Επικόλληση) + +Παρακάτω βρίσκεται το πλήρες, έτοιμο‑για‑εκτέλεση πρόγραμμα. Αντικαταστήστε το `YOUR_DIRECTORY` με έναν πραγματικό φάκελο στο μηχάνημά σας. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Εκτελέστε την κλάση, και θα λάβετε ένα PNG που σέβεται τη ρύθμιση **πώς να ορίσετε dpi** που καθορίσατε. + +## Συμπέρασμα + +Περπατήσαμε μέσα από το **πώς να ορίσετε dpi** όταν **αποδίδετε HTML σε PNG**, καλύψαμε το βήμα **ορισμού μεγέθους viewport** και σας δείξαμε πώς να **αποθηκεύσετε HTML ως PNG** χρησιμοποιώντας το Aspose.HTML για Java. Τα βασικά συμπεράσματα είναι: + +- Χρησιμοποιήστε ένα **sandbox** για έλεγχο DPI και viewport. +- Επιλέξτε τις σωστές **ImageSaveOptions** για lossless έξοδο. +- Επαληθεύστε τα μεταδεδομένα DPI αν χρειάζεται να εγγυηθείτε την ποιότητα εκτύπωσης. + +Από εδώ μπορείτε να πειραματιστείτε με διαφορετικές τιμές DPI, μεγαλύτερα viewports, ή ακόμη και να επεξεργαστείτε κατά παρτίδες μια λίστα URLs. Θέλετε να μετατρέψετε ολόκληρη μια ιστοσελίδα σε μικρογραφίες PNG; Απλώς κάντε βρόχο πάνω σε έναν πίνακα URLs και επαναχρησιμοποιήστε την ίδια διαμόρφωση sandbox. + +Καλή απόδοση, και εύχομαι οι στιγμιότυπές σας να είναι πάντα pixel‑perfect! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/hindi/java/conversion-html-to-various-image-formats/_index.md b/html/hindi/java/conversion-html-to-various-image-formats/_index.md index dd5878459..8396266ec 100644 --- a/html/hindi/java/conversion-html-to-various-image-formats/_index.md +++ b/html/hindi/java/conversion-html-to-various-image-formats/_index.md @@ -110,6 +110,9 @@ Aspose.HTML for Java के साथ HTML को JPEG में कैसे ### [HTML को PNG में बदलना](./convert-html-to-png/) Aspose.HTML के साथ Java में HTML को PNG इमेज में कैसे बदलें सीखें। चरण‑दर‑चरण निर्देशों के साथ एक व्यापक गाइड। +### [dpi सेट कैसे करें – AsposeHTML के साथ HTML को PNG में रेंडर करें](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Aspose.HTML for Java का उपयोग करके PNG आउटपुट की DPI सेट करने की प्रक्रिया सीखें। + ### [HTML को TIFF में बदलना](./convert-html-to-tiff/) Aspose.HTML for Java का उपयोग करके HTML को TIFF में आसानी से कैसे बदलें सीखें। प्रभावी दस्तावेज़ हैंडलिंग के लिए चरण‑दर‑चरण गाइड। diff --git a/html/hindi/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/hindi/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..9a29b4997 --- /dev/null +++ b/html/hindi/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: URL को PNG में बदलते समय DPI कैसे सेट करें। Aspose.HTML का उपयोग करके + Java में HTML को PNG में रेंडर करना, व्यूपोर्ट आकार सेट करना, और HTML को PNG के + रूप में सहेजना सीखें। +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: hi +og_description: URL को PNG में बदलते समय DPI कैसे सेट करें। HTML को PNG में रेंडर + करने, व्यूपोर्ट आकार नियंत्रित करने, और Aspose.HTML का उपयोग करके HTML को PNG के + रूप में सहेजने के लिए चरण‑दर‑चरण गाइड। +og_title: DPI कैसे सेट करें – AsposeHTML के साथ HTML को PNG में रेंडर करें +tags: +- AsposeHTML +- Java +- image rendering +title: dpi कैसे सेट करें – AsposeHTML के साथ HTML को PNG में रेंडर करें +url: /hi/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# DPI सेट करने का तरीका – AsposeHTML के साथ HTML को PNG में रेंडर करना + +क्या आप कभी सोचते थे कि वेब पेज से उत्पन्न स्क्रीनशॉट‑जैसी इमेज के लिए **DPI कैसे सेट करें**? शायद आपको प्रिंट के लिए 300 DPI PNG चाहिए, या मोबाइल ऐप के लिए लो‑रेज़ थंबनेल चाहिए। किसी भी स्थिति में, ट्रिक यह है कि रेंडरिंग इंजन को वह लॉजिकल DPI बताएं जो आप चाहते हैं, फिर इसे बाकी काम करने दें। + +इस ट्यूटोरियल में हम एक लाइव URL लेंगे, उसे PNG फ़ाइल में रेंडर करेंगे, **व्यूपोर्ट साइज सेट करेंगे**, DPI समायोजित करेंगे, और अंत में **HTML को PNG के रूप में सेव करेंगे**—सभी Aspose.HTML for Java के साथ। कोई बाहरी ब्राउज़र नहीं, कोई गड़बड़ कमांड‑लाइन टूल नहीं—सिर्फ साफ़ Java कोड जिसे आप किसी भी Maven या Gradle प्रोजेक्ट में डाल सकते हैं। + +> **Pro tip:** यदि आप केवल एक त्वरित थंबनेल चाहते हैं, तो DPI को 96 DPI (अधिकांश स्क्रीन का डिफ़ॉल्ट) पर रख सकते हैं। प्रिंट‑रेडी एसेट्स के लिए इसे 300 DPI या उससे अधिक कर दें। + +![DPI सेट करने का उदाहरण](https://example.com/images/how-to-set-dpi.png "DPI सेट करने का उदाहरण") + +## आपको क्या चाहिए + +- **Java 17** (या कोई भी नया JDK)। +- **Aspose.HTML for Java** 24.10 या नया। आप इसे Maven Central से प्राप्त कर सकते हैं: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- लक्ष्य पेज को प्राप्त करने के लिए इंटरनेट कनेक्शन (उदाहरण में `https://example.com/sample.html` उपयोग किया गया है)। +- आउटपुट फ़ोल्डर में लिखने की अनुमति। + +बस इतना ही—कोई Selenium नहीं, कोई हेडलेस Chrome नहीं। Aspose.HTML प्रोसेस के भीतर रेंडरिंग करता है, जिसका मतलब है कि आप JVM के अंदर ही रहते हैं और ब्राउज़र लॉन्च करने के ओवरहेड से बचते हैं। + +## चरण 1 – URL से HTML दस्तावेज़ लोड करें + +पहले हम एक `HTMLDocument` इंस्टेंस बनाते हैं जो उस पेज की ओर इशारा करता है जिसे हम कैप्चर करना चाहते हैं। कंस्ट्रक्टर स्वचालित रूप से HTML डाउनलोड करता है, उसे पार्स करता है, और DOM तैयार करता है। + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*क्यों यह महत्वपूर्ण है:* दस्तावेज़ को सीधे लोड करके, आप अलग HTTP क्लाइंट की आवश्यकता को छोड़ देते हैं। Aspose.HTML रीडायरेक्ट, कुकीज़, और यहां तक कि बेसिक ऑथेंटिकेशन का भी सम्मान करता है यदि आप URL में क्रेडेंशियल एम्बेड करते हैं। + +## चरण 2 – इच्छित DPI और व्यूपोर्ट के साथ सैंडबॉक्स बनाएं + +एक **sandbox** Aspose.HTML का तरीका है ब्राउज़र वातावरण की नकल करने का। यहाँ हम इसे बताते हैं कि यह 1280 × 720 स्क्रीन की तरह व्यवहार करे और, सबसे महत्वपूर्ण, हम **डिवाइस DPI** सेट करते हैं। DPI बदलने से रेंडर की गई इमेज की पिक्सेल घनत्व बदलती है बिना लॉजिकल साइज को बदले। + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*आप इन मानों को क्यों बदल सकते हैं:* +- **Viewport size** नियंत्रित करता है कि CSS मीडिया क्वेरीज़ (`@media (max-width: …)`) कैसे व्यवहार करती हैं। +- **Device DPI** प्रिंट होने पर इमेज के भौतिक आकार को प्रभावित करता है। 96 DPI इमेज स्क्रीन पर ठीक दिखती है; 300 DPI इमेज कागज पर स्पष्टता बनाए रखती है। + +यदि आपको वर्गाकार थंबनेल चाहिए, तो बस `setViewportSize(500, 500)` बदलें और DPI को कम रखें। + +## चरण 3 – आउटपुट फ़ॉर्मेट के रूप में PNG चुनें + +Aspose.HTML कई रास्टर फ़ॉर्मेट्स (PNG, JPEG, BMP, GIF) को सपोर्ट करता है। PNG लॉस‑लेस है, जिससे यह उन स्क्रीनशॉट्स के लिए उपयुक्त है जहाँ आप हर पिक्सेल को संरक्षित रखना चाहते हैं। + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +यदि आप फ़ाइल आकार को लेकर चिंतित हैं तो आप कम्प्रेशन लेवल (`pngOptions.setCompressionLevel(9)`) भी बदल सकते हैं। + +## चरण 4 – इमेज को रेंडर और सेव करें + +अब हम दस्तावेज़ को **सेव** करने के लिए कहते हैं कि वह खुद को इमेज के रूप में सेव करे। `save` मेथड एक फ़ाइल पाथ और पहले कॉन्फ़िगर किए गए विकल्प लेता है। + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +जब प्रोग्राम समाप्त होगा, आपको `YOUR_DIRECTORY/sandboxed.png` पर एक PNG फ़ाइल मिलेगी। इसे खोलें—यदि आपने DPI को 300 सेट किया है, तो इमेज मेटाडेटा में वह दिखेगा, भले ही पिक्सेल डाइमेंशन 1280 × 720 ही रहे। + +## चरण 5 – DPI सत्यापित करें (वैकल्पिक लेकिन उपयोगी) + +यदि आप दोबारा जाँचना चाहते हैं कि DPI वास्तव में लागू हुआ है, तो आप **metadata‑extractor** जैसी हल्की लाइब्रेरी से PNG मेटाडेटा पढ़ सकते हैं: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +आपको कंसोल पर `300` (या जो भी आपने सेट किया हो) प्रिंट हुआ दिखेगा। यह कदम रेंडरिंग के लिए आवश्यक नहीं है, लेकिन यह एक त्वरित सत्यापन है, विशेषकर जब आप प्रिंट वर्कफ़्लो के लिए एसेट्स बना रहे हों। + +## सामान्य प्रश्न और किनारे के मामलों + +### “यदि पेज कंटेंट लोड करने के लिए JavaScript का उपयोग करता है?” + +Aspose.HTML **सीमित उपसमुच्चय** का JavaScript चलाता है। अधिकांश स्थैतिक साइटों के लिए यह तुरंत काम करता है। यदि पेज क्लाइंट‑साइड फ्रेमवर्क्स (React, Angular, Vue) पर बहुत अधिक निर्भर करता है, तो आपको पेज को प्री‑रेंडर करने या इसके बजाय हेडलेस ब्राउज़र का उपयोग करने की आवश्यकता हो सकती है। हालांकि, एक बार DOM तैयार हो जाने पर DPI सेट करना उसी तरह काम करता है। + +### “क्या मैं PNG के बजाय PDF रेंडर कर सकता हूँ?” + +बिल्कुल। `ImageSaveOptions` को `PdfSaveOptions` से बदलें और आउटपुट एक्सटेंशन को `.pdf` कर दें। DPI सेटिंग अभी भी एम्बेडेड इमेजेज़ की रास्टराइज्ड उपस्थिति को प्रभावित करती है। + +### “रेटिना डिस्प्ले के लिए हाई‑रेज़ोल्यूशन स्क्रीनशॉट्स के बारे में क्या?” + +सिर्फ व्यूपोर्ट डाइमेंशन को दुगना करें जबकि DPI को 96 DPI पर रखें, या व्यूपोर्ट को वैसा ही रखें और DPI को 192 तक बढ़ा दें। resulting PNG में दोगुने पिक्सेल होंगे, जिससे आपको वह स्पष्ट रेटिना फ़ील मिलेगा। + +### “क्या मुझे रिसोर्सेज़ को साफ़ करना चाहिए?” + +`HTMLDocument` `AutoCloseable` को इम्प्लीमेंट करता है। प्रोडक्शन ऐप में, इसे try‑with‑resources ब्लॉक में रैप करें: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## पूर्ण कार्यशील उदाहरण (कॉपी‑पेस्ट तैयार) + +नीचे पूरा, रन‑तैयार प्रोग्राम दिया गया है। `YOUR_DIRECTORY` को अपने मशीन पर वास्तविक फ़ोल्डर से बदलें। + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +क्लास चलाएँ, और आपको एक PNG मिलेगा जो आपके द्वारा निर्दिष्ट **DPI सेट करने** सेटिंग का सम्मान करता है। + +## निष्कर्ष + +हमने **DPI सेट करने** के बारे में बताया जब आप **HTML को PNG में रेंडर** करते हैं, **व्यूपोर्ट साइज सेट** करने के चरण को कवर किया, और दिखाया कि कैसे **HTML को PNG के रूप में सेव** करें Aspose.HTML for Java का उपयोग करके। मुख्य बिंदु हैं: + +- DPI और व्यूपोर्ट को नियंत्रित करने के लिए **sandbox** का उपयोग करें। +- लॉसलेस आउटपुट के लिए सही **ImageSaveOptions** चुनें। +- यदि आपको प्रिंट क्वालिटी की गारंटी चाहिए तो DPI मेटाडेटा को सत्यापित करें। + +अब आप विभिन्न DPI मानों, बड़े व्यूपोर्ट, या यहाँ तक कि URL की सूची को बैच‑प्रोसेस करने के साथ प्रयोग कर सकते हैं। पूरी वेबसाइट को PNG थंबनेल में बदलना चाहते हैं? बस URL की एरे पर लूप करें और वही sandbox कॉन्फ़िगरेशन पुनः उपयोग करें। + +रेंडरिंग का आनंद लें, और आपके स्क्रीनशॉट हमेशा पिक्सेल‑परफेक्ट रहें! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/hongkong/java/conversion-html-to-various-image-formats/_index.md b/html/hongkong/java/conversion-html-to-various-image-formats/_index.md index 811ab5efb..bded31e8e 100644 --- a/html/hongkong/java/conversion-html-to-various-image-formats/_index.md +++ b/html/hongkong/java/conversion-html-to-various-image-formats/_index.md @@ -96,6 +96,9 @@ weight: 24 ### [將 HTML 轉換為 TIFF](./convert-html-to-tiff/) 了解如何使用 Aspose.HTML for Java 輕鬆將 HTML 轉換為 TIFF。提供高效的文件處理步驟說明。 +### [如何設定 DPI – 使用 AsposeHTML 渲染 HTML 為 PNG](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +說明如何在 AsposeHTML 中設定 DPI,以將 HTML 渲染為高解析度 PNG 圖像。 + ## 常見問題集 **Q: 我可以在 Java 中將 HTML 轉換為 PNG 而不使用額外的圖像函式庫嗎?** diff --git a/html/hongkong/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/hongkong/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..763fb9682 --- /dev/null +++ b/html/hongkong/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,222 @@ +--- +category: general +date: 2026-01-14 +description: 將 URL 轉換為 PNG 時如何設定 DPI。學習使用 Aspose.HTML 在 Java 中將 HTML 渲染為 PNG、設定視口大小,並將 + HTML 儲存為 PNG。 +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: zh-hant +og_description: 將 URL 轉換為 PNG 時如何設定 DPI。一步一步的指南,說明如何將 HTML 渲染為 PNG、控制視口大小,以及使用 Aspose.HTML + 將 HTML 儲存為 PNG。 +og_title: 如何設定 DPI – 使用 AsposeHTML 將 HTML 渲染為 PNG +tags: +- AsposeHTML +- Java +- image rendering +title: 如何設定 DPI – 使用 AsposeHTML 將 HTML 渲染為 PNG +url: /zh-hant/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# 如何設定 DPI – 使用 AsposeHTML 將 HTML 渲染為 PNG + +有沒有想過 **如何設定 DPI** 以產生類似螢幕截圖的網頁圖像?也許你需要 300 DPI 的 PNG 以供列印,或是低解析度的縮圖供手機應用程式使用。無論哪種情況,關鍵在於告訴渲染引擎你想要的邏輯 DPI,然後讓它自行處理。 + +在本教學中,我們將使用實際的 URL,將其渲染為 PNG 檔案,**設定視口大小**,調整 DPI,最後 **將 HTML 儲存為 PNG**——全部使用 Aspose.HTML for Java。無需外部瀏覽器,無需繁雜的命令列工具——只要乾淨的 Java 程式碼,隨時可放入任何 Maven 或 Gradle 專案中。 + +> **專業提示:** 如果你只需要快速產生縮圖,可以保持 DPI 為 96 DPI(大多數螢幕的預設值)。若是列印用的素材,則建議提升至 300 DPI 或更高。 + +![設定 DPI 範例](https://example.com/images/how-to-set-dpi.png "設定 DPI 範例") + +## 您需要的環境 + +- **Java 17**(或任何較新的 JDK)。 +- **Aspose.HTML for Java** 24.10 或更新版本。您可以從 Maven Central 取得: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- 需要網際網路連線以下載目標頁面(範例使用 `https://example.com/sample.html`)。 +- 需要對輸出資料夾具有寫入權限。 + +就是這樣——不需要 Selenium,也不需要無頭 Chrome。Aspose.HTML 於程式內部完成渲染,意味著您仍在 JVM 內部執行,避免了啟動瀏覽器的額外開銷。 + +## 步驟 1 – 從 URL 載入 HTML 文件 + +首先,我們建立指向欲擷取頁面的 `HTMLDocument` 實例。建構子會自動下載 HTML、解析並準備 DOM。 + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*為什麼這很重要:* 直接載入文件即可省去額外的 HTTP 客戶端。Aspose.HTML 會遵守重新導向、Cookie,甚至在 URL 中嵌入的基本驗證。 + +## 步驟 2 – 建立具備目標 DPI 與視口的 Sandbox + +**Sandbox** 是 Aspose.HTML 模擬瀏覽器環境的方式。在此我們讓它假裝是一個 1280 × 720 的螢幕,且最重要的是設定 **裝置 DPI**。變更 DPI 會改變渲染圖像的像素密度,而不會改變邏輯尺寸。 + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*為什麼可能需要調整這些值:* +- **視口大小** 會影響 CSS 媒體查詢 (`@media (max-width: …)`) 的行為。 +- **裝置 DPI** 會影響列印時圖像的實體尺寸。96 DPI 圖像在螢幕上看起來不錯;300 DPI 圖像在紙張上則保持清晰。 + +如果需要正方形縮圖,只需將 `setViewportSize(500, 500)` 改為相同的寬高,並保持較低的 DPI。 + +## 步驟 3 – 選擇 PNG 作為輸出格式 + +Aspose.HTML 支援多種點陣圖格式(PNG、JPEG、BMP、GIF)。PNG 為無損格式,非常適合需要完整保留每個像素的螢幕截圖。 + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +如果在意檔案大小,也可以調整壓縮等級(`pngOptions.setCompressionLevel(9)`)。 + +## 步驟 4 – 渲染並儲存圖像 + +現在我們指示文件 **儲存** 為圖像。`save` 方法接受檔案路徑以及先前設定好的選項。 + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +程式執行完畢後,您會在 `YOUR_DIRECTORY/sandboxed.png` 找到 PNG 檔案。開啟它——如果您將 DPI 設為 300,圖像的中繼資料會顯示該 DPI,儘管像素尺寸仍為 1280 × 720。 + +## 步驟 5 – 驗證 DPI(可選但實用) + +如果想再次 DPI 是否真的套用,可使用輕量級函式庫 **metadata‑extractor** 讀取 PNG 中繼資料: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +您應該會在主控台看到 `300`(或您設定的數值)被印出。此步驟對渲染不是必須的,但作為快速的正確性檢查相當有用,尤其在產出列印工作流程的資產時。 + +## 常見問題與邊緣情況 + +### 「如果頁面使用 JavaScript 載入內容?」 + +Aspose.HTML 會執行 **受限的 JavaScript 子集**。對於大多數靜態網站,它可直接運作。若頁面大量依賴客戶端框架(React、Angular、Vue),可能需要先行預渲染頁面或改用無頭瀏覽器。然而,一旦 DOM 準備好,設定 DPI 的方式相同。 + +### 「我可以渲染 PDF 而非 PNG 嗎?」 + +當然可以。將 `ImageSaveOptions` 換成 `PdfSaveOptions`,並將輸出副檔名改為 `.pdf`。DPI 設定仍會影響任何嵌入圖像的點陣化外觀。 + +### 「高解析度螢幕(Retina)截圖該怎麼做?」 + +只要將視口尺寸加倍,同時保持 DPI 為 96 DPI,或保持視口不變並將 DPI 提升至 192。產生的 PNG 會有兩倍的像素,呈現出清晰的 Retina 效果。 + +### 「我需要清理資源嗎?」 + +`HTMLDocument` 實作了 `AutoCloseable`。在正式應用中,請將其包在 try‑with‑resources 區塊中: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## 完整可執行範例(直接複製貼上) + +以下是完整、可直接執行的程式。請將 `YOUR_DIRECTORY` 替換為您機器上的實際資料夾路徑。 + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +執行此類別,即可取得符合您所指定 **如何設定 DPI** 設定的 PNG。 + +## 結論 + +我們已說明在 **將 HTML 渲染為 PNG** 時 **如何設定 DPI**,涵蓋了 **設定視口大小** 的步驟,並示範了如何使用 Aspose.HTML for Java **將 HTML 儲存為 PNG**。主要重點如下: + +- 使用 **sandbox** 來控制 DPI 與視口。 +- 為無損輸出選擇適當的 **ImageSaveOptions**。 +- 如需確保列印品質,請驗證 DPI 中繼資料。 + +從此您可以嘗試不同的 DPI 值、較大的視口,甚至批次處理多個 URL。想將整個網站轉換為 PNG 縮圖?只需對 URL 陣列迴圈,重複使用相同的 sandbox 設定即可。 + +祝渲染順利,願您的螢幕截圖永遠保持像素完美! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/hungarian/java/conversion-html-to-various-image-formats/_index.md b/html/hungarian/java/conversion-html-to-various-image-formats/_index.md index 198b3fd8d..75e909ab1 100644 --- a/html/hungarian/java/conversion-html-to-various-image-formats/_index.md +++ b/html/hungarian/java/conversion-html-to-various-image-formats/_index.md @@ -98,6 +98,8 @@ Tanulja meg, hogyan konvertálhat HTML‑t JPEG‑be az Aspose.HTML for Java seg Ismerje meg, hogyan konvertálhat HTML‑t PNG képekké Java‑ban az Aspose.HTML használatával. Átfogó útmutató részletes instrukciókkal. ### [HTML átalakítása TIFF‑be](./convert-html-to-tiff/) Tanulja meg, hogyan konvertálhat HTML‑t TIFF‑be az Aspose.HTML for Java segítségével. Lépésről‑lépésre útmutató a hatékony dokumentumkezeléshez. +### [hogyan állítsa be a DPI‑t – HTML renderelése PNG‑be az AsposeHTML segítségével](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Ismerje meg, hogyan állíthatja be a DPI‑t a PNG képekhez az Aspose.HTML használatával, hogy magas felbontású képernyőképeket kapjon. ## Gyakran ismételt kérdések diff --git a/html/hungarian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/hungarian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..8bb1cc1aa --- /dev/null +++ b/html/hungarian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: hogyan állítsuk be a DPI-t URL PNG-re konvertálásakor. Tanulja meg, hogyan + rendereljük a HTML-t PNG-re, állítsuk be a nézetablak méretét, és mentsük a HTML-t + PNG-ként az Aspose.HTML Java használatával. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: hu +og_description: Hogyan állítsuk be a DPI-t URL PNG-re konvertálásakor. Lépésről lépésre + útmutató a HTML PNG-re rendereléséhez, a nézetablak méretének szabályozásához és + a HTML PNG-ként mentéséhez az Aspose.HTML segítségével. +og_title: hogyan állítsuk be a dpi-t – HTML renderelése PNG-be az AsposeHTML segítségével +tags: +- AsposeHTML +- Java +- image rendering +title: hogyan állítsuk be a DPI-t – HTML renderelése PNG‑be az AsposeHTML‑kel +url: /hu/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# hogyan állítsuk be a DPI-t – HTML renderelése PNG-be az AsposeHTML segítségével + +Valaha is elgondolkodtál már azon, **hogyan állítsuk be a DPI-t** egy weboldalról generált képernyőképszerű képhez? Lehet, hogy 300 DPI-s PNG-re van szükséged nyomtatáshoz, vagy egy alacsony felbontású bélyegképre mobilalkalmazáshoz. Bármelyik esetben a trükk, hogy megmondjuk a renderelő motornak, milyen logikai DPI-t szeretnénk, majd hagyjuk, hogy elvégezze a nehéz munkát. + +Ebben az útmutatóban egy élő URL-t fogunk felhasználni, rendereljük PNG fájlba, **beállítjuk a viewport méretét**, módosítjuk a DPI-t, és végül **HTML-t mentünk PNG‑ként** – mindezt az Aspose.HTML for Java segítségével. Nincs külső böngésző, nincs bonyolult parancssori eszköz – csak tiszta Java kód, amelyet bármely Maven vagy Gradle projektbe beilleszthetsz. + +> **Pro tipp:** Ha csak egy gyors bélyegképre van szükséged, a DPI-t hagyhatod 96 DPI‑n (a legtöbb képernyő alapértelmezett értéke). Nyomtatásra kész anyagok esetén emeld 300 DPI‑ra vagy magasabbra. + +![hogyan állítsuk be a DPI példája](https://example.com/images/how-to-set-dpi.png "hogyan állítsuk be a DPI példája") + +## Amire szükséged lesz + +- **Java 17** (vagy bármely friss JDK). +- **Aspose.HTML for Java** 24.10 vagy újabb. Letöltheted a Maven Central‑ról: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Internetkapcsolat a céloldal lekéréséhez (a példa a `https://example.com/sample.html` URL‑t használja). +- Írási jogosultság a kimeneti mappához. + +Ennyi – nincs Selenium, nincs headless Chrome. Az Aspose.HTML a renderelést a folyamaton belül végzi, ami azt jelenti, hogy a JVM‑en belül maradsz, és elkerülöd a böngésző indításának terheit. + +## 1. lépés – HTML dokumentum betöltése URL‑ről + +Először létrehozunk egy `HTMLDocument` példányt, amely a rögzíteni kívánt oldalra mutat. A konstruktor automatikusan letölti a HTML‑t, feldolgozza, és előkészíti a DOM‑ot. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Miért fontos:* A dokumentum közvetlen betöltésével elkerülöd egy külön HTTP kliens használatát. Az Aspose.HTML tiszteletben tartja az átirányításokat, sütiket, és még az alapvető hitelesítést is, ha a URL‑ben adod meg a hitelesítő adatokat. + +## 2. lépés – Sandbox létrehozása a kívánt DPI‑val és viewporttal + +A **sandbox** az Aspose.HTML módja annak, hogy egy böngésző környezetet utánozzon. Itt azt mondjuk neki, mintha egy 1280 × 720 képernyő lenne, és, ami kulcsfontosságú, beállítjuk a **eszköz DPI‑t**. A DPI módosítása megváltoztatja a renderelt kép pixel sűrűségét anélkül, hogy a logikai méretet befolyásolná. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Miért érdemes ezeket az értékeket módosítani:* +- **Viewport méret** szabályozza, hogy a CSS média lekérdezések (`@media (max-width: …)`) hogyan viselkednek. +- **Eszköz DPI** befolyásolja a kép fizikai méretét nyomtatáskor. Egy 96 DPI‑s kép jól néz ki a képernyőkön; egy 300 DPI‑s kép megőrzi a tisztaságot papíron. + +Ha négyzet alakú bélyegképre van szükséged, egyszerűen módosítsd a `setViewportSize(500, 500)` értéket, és tartsd alacsonyan a DPI‑t. + +## 3. lépés – PNG kiválasztása kimeneti formátumként + +Az Aspose.HTML több raszteres formátumot támogat (PNG, JPEG, BMP, GIF). A PNG veszteségmentes, ami tökéletesé teszi képernyőképekhez, ahol minden pixel megőrzése fontos. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +A tömörítési szintet is módosíthatod (`pngOptions.setCompressionLevel(9)`), ha a fájlméret aggaszt. + +## 4. lépés – Kép renderelése és mentése + +Most azt mondjuk a dokumentumnak, hogy **mentse** magát képként. A `save` metódus egy fájlútvonalat és a korábban beállított opciókat várja. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Amikor a program befejeződik, a `YOUR_DIRECTORY/sandboxed.png` helyen találsz egy PNG fájlt. Nyisd meg – ha a DPI‑t 300‑ra állítottad, a kép metaadatai ezt tükrözik, bár a pixelméretek továbbra is 1280 × 720 maradnak. + +## 5. lépés – DPI ellenőrzése (opcionális, de hasznos) + +Ha szeretnéd duplán ellenőrizni, hogy a DPI valóban alkalmazva lett, beolvashatod a PNG metaadatait egy könnyű könyvtárral, például a **metadata‑extractor**‑ral: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +A konzolon a `300` (vagy amit beállítottál) értéket kell látnod. Ez a lépés nem kötelező a rendereléshez, de gyors ellenőrzés, különösen, ha nyomtatási munkafolyamatokhoz generálsz anyagokat. + +## Gyakori kérdések és speciális esetek + +### „Mi van, ha az oldal JavaScript‑et használ a tartalom betöltéséhez?” + +Az Aspose.HTML egy **korlátozott részhalmazt** hajt végre a JavaScript‑ből. A legtöbb statikus oldalnál azonnal működik. Ha az oldal erősen támaszkodik kliens‑oldali keretrendszerekre (React, Angular, Vue), előfordulhat, hogy előre kell renderelned az oldalt, vagy helyette headless böngészőt kell használnod. A DPI beállítása azonban ugyanúgy működik, amint a DOM készen áll. + +### „Renderelhetek PDF‑et PNG helyett?” + +Természetesen. Cseréld le a `ImageSaveOptions`‑t `PdfSaveOptions`‑ra, és módosítsd a kimeneti kiterjesztést `.pdf`‑re. A DPI beállítás továbbra is befolyásolja a beágyazott képek raszteres megjelenését. + +### „Mi a helyzet a magas felbontású képernyőképekkel a retina kijelzőkhöz?” + +Egyszerűen duplázd meg a viewport méreteit, miközben a DPI‑t 96 DPI‑n tartod, vagy tartsd a viewportot, és emeld a DPI‑t 192‑re. Az eredményül kapott PNG kétszer annyi pixelt tartalmaz, így a retina hatást érheted el. + +### „ Szükséges erőforrásokat felszabadítani?” + +`HTMLDocument` implements `AutoCloseable`. In a production app, wrap it in a try‑with‑resources block: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Ez biztosítja, hogy a natív erőforrások gyorsan felszabaduljanak. + +## Teljes működő példa (másolás‑beillesztés kész) + +Az alábbiakban a teljes, futtatható program látható. Cseréld le a `YOUR_DIRECTORY`‑t egy valós mappára a gépeden. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Futtasd az osztályt, és kapsz egy PNG‑t, amely tiszteletben tartja a megadott **dpi beállítást**. + +## Összegzés + +Áttekintettük, **hogyan állítsuk be a DPI‑t**, amikor **HTML‑t renderelünk PNG‑be**, lefedtük a **viewport méret beállítása** lépést, és megmutattuk, hogyan **menthetünk HTML‑t PNG‑ként** az Aspose.HTML for Java segítségével. A fő tanulságok: + +- Használj **sandbox‑ot** a DPI és a viewport vezérléséhez. +- Válaszd a megfelelő **ImageSaveOptions**‑t a veszteségmentes kimenethez. +- Ellenőrizd a DPI metaadatokat, ha a nyomtatási minőséget garantálni szeretnéd. + +Innen tovább kísérletezhetsz különböző DPI értékekkel, nagyobb viewportokkal, vagy akár tömegesen feldolgozhatsz egy URL‑listát. Szeretnél egy egész weboldalt PNG bélyegképekké konvertálni? Csak iterálj egy URL‑tömbön, és használd újra ugyanazt a sandbox konfigurációt. + +Boldog renderelést, és legyenek a képernyőképeid mindig pixel‑tökéletesek! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/hungarian/java/css-html-form-editing/_index.md b/html/hungarian/java/css-html-form-editing/_index.md index 37f6daf8c..13bc6deeb 100644 --- a/html/hungarian/java/css-html-form-editing/_index.md +++ b/html/hungarian/java/css-html-form-editing/_index.md @@ -30,9 +30,11 @@ Most váltsunk sebességet, és fedezzük fel, hogyan lehet hatékonyan szerkesz Tanulja meg, hogyan használhatja az Aspose.HTML for Java-t fejlett CSS-technikák alkalmazására, beleértve az egyéni oldalmargókat és a dinamikus tartalmat. Részletes, gyakorlati útmutató fejlesztőknek. ### [HTML űrlap szerkesztése és benyújtása Aspose.HTML for Java segítségével](./html-form-editing/) Ebből az átfogó, lépésenkénti útmutatóból megtudhatja, hogyan szerkeszthet és küldhet be programozott HTML-űrlapokat az Aspose.HTML for Java használatával. +### [Hogyan kapja meg a stílust Java-ban – HTML betöltése és lekérdező szelektor](./how-to-get-style-in-java-load-html-query-selector/) +Ismerje meg, hogyan tölthet be HTML-t Java-ban, és használhatja a query selector-t a stílusok lekérdezéséhez. {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/hungarian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/hungarian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..94ea2b6f0 --- /dev/null +++ b/html/hungarian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,183 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: hu +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /hu/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# hogyan lehet lekérni a stílust Java‑ban – HTML betöltése és query selector + +Ever wondered **how to get style** of an element when you’re parsing HTML with Java? Maybe you’re building a scraper, a testing tool, or just need to verify visual cues in a generated page. The good news is that Aspose.HTML makes this a piece of cake. In this tutorial we’ll walk through loading an HTML document, using a **query selector example**, and finally reading the **background-color property** of a `
` element. No magic, just clear Java code you can copy‑paste and run. + +## Amire szükséged lesz + +* **Java 17** (vagy bármely friss JDK) – az API Java 8+ verzióval működik, de az újabb verziók jobb teljesítményt nyújtanak. +* **Aspose.HTML for Java** könyvtár – letöltheted a Maven Central‑ról (`com.aspose:aspose-html:23.10` a jelenlegi írás időpontjában). +* Egy kis HTML fájl (`input.html`), amely legalább egy `
` elemet tartalmaz, amelynek a CSS `background-color` értéke be van állítva inline vagy egy stíluslapon. + +Ez minden. Nincs extra keretrendszer, nincs nehéz böngésző, csak tiszta Java és Aspose.HTML. + +## 1. lépés: HTML dokumentum betöltése + +Az első dolog, amit meg kell tenned, az **load html document** betöltése a memóriába. Az Aspose.HTML `HTMLDocument` osztálya elrejti a fájlrendszer kezelését, és egy DOM‑ot ad, amelyet lekérdezhetsz. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Why this matters:** Loading the document creates a parsed DOM tree, which is the foundation for any subsequent CSS or JavaScript evaluation. If the file can’t be found, Aspose throws a descriptive `FileNotFoundException`, so double‑check the path. + +### Profi tipp +If you’re pulling HTML from a URL instead of a file, just pass the URL string to the constructor – Aspose handles the HTTP request for you. + +## 2. lépés: Query selector példa használata + +Now that the document is in memory, let’s **query selector example** to grab the first `
` element. The `querySelector` method mirrors the CSS selector syntax you already know from the browser. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Why this matters:** `querySelector` returns the first matching node, which is perfect when you only need a single element’s style. If you need multiple elements, `querySelectorAll` returns a `NodeList`. + +### Szél eset +If the selector doesn’t match anything, `divElement` will be `null`. Always guard against that before you try to read styles: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## 3. lépés: Számított stílus lekérése + +With the element in hand, the next step is to **parse html java** enough to compute the final CSS values. Aspose.HTML does the heavy lifting: it resolves cascade, inheritance, and even external stylesheets. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Why this matters:** The computed style reflects the exact values the browser would apply after processing all CSS rules. It’s more reliable than reading the raw `style` attribute, which may be incomplete. + +## 4. lépés: A background‑color tulajdonság lekérése + +Finally, we pull the **background-color property** we care about. The `getPropertyValue` method returns the value as a string (e.g., `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **What you’ll see:** If your `
` had `background-color: #ff5733;` either inline or via a stylesheet, the console will output something like `Computed background‑color: rgb(255, 87, 51)`. + +### Gyakori buktató +When the property isn’t defined, `getPropertyValue` returns an empty string. That’s a cue to either fall back to a default or inspect the element’s parent styles. + +## Teljes működő példa + +Putting it all together, here’s the complete, ready‑to‑run program: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Várható kimenet (példa):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +If the `
` has no background color set, the output will be an empty line – that’s your signal to look at inherited styles. + +## Tippek, trükkök és figyelmeztetések + +| Helyzet | Mit kell tenni | +|-----------|------------| +| **Több `
` elem** | Használd a `querySelectorAll("div")`‑t, és iterálj a `NodeList`‑en. | +| **Külső CSS fájlok** | Győződj meg róla, hogy a HTML fájl helyes útvonalakkal hivatkozik rájuk; az Aspose.HTML automatikusan betölti őket. | +| **Csak inline `style` attribútum** | `getComputedStyle` továbbra is működik – egyesíti az inline stílusokat az alapértelmezettekkel. | +| **Teljesítménybeli aggályok** | Töltsd be a dokumentumot egyszer, és használd újra a `HTMLDocument` objektumot, ha sok elemet kell lekérdezni. | +| **Androidon futtatás** | Az Aspose.HTML for Java támogatja az Androidot, de be kell illeszteni az Android‑specifikus AAR‑t. | + +## Kapcsolódó témák, amiket érdemes felfedezni + +* **HTML elemzés Jsoup‑pal vs. Aspose.HTML** – mikor melyiket válaszd. +* **Számított stílusok exportálása JSON‑ba** – hasznos API‑vezérelt front‑endekhez. +* **Képernyőképek automatikus generálása** – kombináld a számított stílusokat az Aspose.PDF‑vel vizuális regressziós teszteléshez. + +--- + +### Következtetés + +You now know **how to get style** of any element when you **load html document** with Aspose.HTML, run a **query selector example**, and extract the **background-color property**. The code is self‑contained, runs on any recent JDK, and gracefully handles missing elements or undefined styles. From here you can extend the approach to fetch font sizes, margins, or even computed values after JavaScript execution (Aspose.HTML also supports script evaluation). + +Give it a whirl, tweak the selector, and see what other CSS treasures you can uncover. Happy coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/indonesian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/indonesian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..50206b7a7 --- /dev/null +++ b/html/indonesian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Create PDF from Markdown in Java using Aspose.HTML – a quick step‑by‑step + tutorial to convert markdown to pdf, save markdown as pdf, and learn java markdown + to pdf basics. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: id +og_description: Create PDF from Markdown in Java with Aspose.HTML. Learn how to convert + markdown to pdf, save markdown as pdf, and handle common edge cases in a concise + tutorial. +og_title: Create PDF from Markdown in Java – Quick One‑Liner +tags: +- Java +- PDF +- Markdown +title: Create PDF from Markdown in Java – Simple One‑Liner Guide +url: /id/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Membuat PDF dari Markdown di Java – Panduan Satu Barisederhana + +Pernah bertanya-tanya bagaimana **membuat PDF dari Markdown** tanpa harus berurusan dengan puluhan pustaka? Anda tidak sendirian. Banyak pengembang perlu mengubah catatan `.md` mereka menjadi PDF yang rapi untuk laporan, dokumentasi, atau e‑book, dan mereka menginginkan solusi yang dapat dijalankan dalam satu baris kode Java. + +Dalam tutorial ini kami akan membahas tepatnya hal itu: menggunakan pustaka Aspose.HTML for Java untuk **mengonversi markdown ke pdf** dan **menyimpan markdown sebagai pdf** dengan cara yang bersih dan dapat dipelihara. Kami juga akan menyentuh topik yang lebih luas tentang **java markdown to pdf** sehingga Anda memahami alasan di balik setiap langkah, bukan hanya caranya. + +> **Apa yang akan Anda dapatkan** +> Sebuah program Java lengkap yang dapat dijalankan, yang membaca `input.md`, menulis `output.pdf`, dan mencetak pesan keberhasilan yang ramah. Selain itu, Anda akan mengetahui cara menyesuaikan konversi, menangani file yang hilang, dan mengintegrasikan kode ke dalam proyek yang lebih besar. + +## Prasyarat – Apa yang Anda Butuhkan Sebelum Memulai + +- **Java Development Kit (JDK) 11 atau lebih baru** – kode ini menggunakan `java.nio.file.Paths`, yang tersedia sejak JDK 7, tetapi JDK 11 adalah LTS saat ini dan memastikan kompatibilitas dengan Aspose.HTML. +- **Aspose.HTML for Java** (versi 23.9 atau lebih baru). Anda dapat mengambilnya dari Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **File Markdown** (`input.md`) yang ditempatkan di lokasi yang dapat Anda referensikan. Jika belum memiliki, buat file kecil dengan beberapa judul dan daftar – pustaka akan menangani semua Markdown yang valid. +- **IDE atau `javac`/`java` biasa** – kami akan menjaga kode tetap murni Java, tanpa Spring atau kerangka kerja lain. + +> **Tips pro:** Jika Anda menggunakan Maven, tambahkan dependensi ke `pom.xml` Anda dan jalankan `mvn clean install`. Jika Anda lebih suka Gradle, setaraannya adalah `implementation 'com.aspose:aspose-html:23.9'`. + +## Gambaran Umum – Membuat PDF dari Markdown dalam Satu Langkah + +Berikut adalah program lengkap yang akan kita bangun. Perhatikan **panggilan tunggal** ke `Converter.convert(...)`; itulah inti dari operasi **create pdf from markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Menjalankan kelas ini akan membaca `input.md`, menghasilkan `output.pdf`, dan menampilkan baris konfirmasi. Itu saja—**seluruh alur kerja `create pdf from markdown` dalam kurang dari 30 baris** (termasuk komentar). + +## Langkah‑per‑Langkah + +### 1️⃣ Tentukan File Sumber dan Tujuan + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Mengapa kami menggunakan `Paths.get`**: Ia membangun path yang independen dari OS, menangani backslash Windows dan slash Unix secara otomatis. +- **Kasus tepi**: Jika file Markdown tidak ada, `Converter.convert` akan melempar `FileNotFoundException`. Anda dapat memeriksa terlebih dahulu dengan `Files.exists(Paths.get(markdownPath))` dan menampilkan pesan error yang ramah. + +### 2️⃣ Siapkan Opsi Penyimpanan PDF (Penyesuaian Opsional) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Perilaku default**: PDF akan menggunakan ukuran halaman A4, margin default, dan menyematkan font secara otomatis. +- **Kustomisasi**: Ingin tata letak lanskap? Gunakan `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Tips performa**: Untuk file Markdown besar, Anda dapat mengaktifkan `pdfOptions.setEmbedStandardFonts(false)` untuk mengurangi ukuran file dengan mengorbankan kemungkinan perbedaan rendering. + +### 3️⃣ Lakukan Konversi – Inti dari “Convert Markdown to PDF” + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **Apa yang terjadi di balik layar**: Aspose.HTML mem-parsing Markdown menjadi DOM HTML internal, lalu merender DOM tersebut ke PDF menggunakan mesin layout berpresisi tinggi. +- **Mengapa ini pendekatan yang direkomendasikan**: Dibandingkan dengan pipeline HTML‑to‑PDF buatan sendiri (misalnya menggunakan wkhtmltopdf), Aspose menangani CSS, tabel, gambar, dan Unicode secara langsung, menjadikan pertanyaan **how to convert markdown** menjadi hal yang sepele. + +### 4️⃣ Pesan Konfirmasi + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +Sentuhan UX kecil—terutama berguna ketika program dijalankan sebagai bagian dari batch job yang lebih besar. + +## Menangani Masalah Umum + +| Masalah | Gejala | Solusi | +|-------|---------|-----| +| **File Markdown tidak ditemukan** | `FileNotFoundException` | Verifikasi path terlebih dahulu: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Gambar tidak didukung** | Gambar muncul sebagai placeholder rusak di PDF | Pastikan gambar direferensikan dengan path absolut atau sematkan sebagai Base64 dalam Markdown. | +| **Dokumen besar menyebabkan OOM** | `OutOfMemoryError` | Tingkatkan heap JVM (`-Xmx2g`) atau bagi Markdown menjadi beberapa bagian dan konversi masing‑masing, lalu gabungkan PDF (Aspose menyediakan penggabungan `PdfFile`). | +| **Font khusus hilang** | Teks dirender dengan font fallback | Instal font yang diperlukan di host atau sematkan secara manual via `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Memperluas Satu Baris: Skenario Dunia Nyata + +### A. Konversi Batch Banyak File + +Jika Anda perlu **menyimpan markdown sebagai pdf** untuk seluruh folder, bungkus konversi dalam loop: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Menambahkan Header/Footer Kustom + +Misalkan Anda ingin setiap halaman menampilkan logo dan nomor halaman. Gunakan `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Sekarang setiap PDF yang dihasilkan membawa branding yang Anda butuhkan—sempurna untuk dokumentasi korporat. + +### C. Mengintegrasikan ke Layanan Spring Boot + +Ekspos konversi sebagai endpoint REST: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +Sekarang kemampuan **java markdown to pdf** tersedia untuk klien mana pun—mobile, web, atau desktop. + +## Output yang Diharapkan + +Setelah menjalankan `MdToPdfOneLiner` asli, Anda akan melihat file baru `output.pdf` di folder yang Anda tentukan. Membukanya akan menampilkan konten Markdown Anda yang dirender dengan judul, daftar, blok kode, dan gambar yang Anda sertakan. PDF sepenuhnya dapat dicari, dan teks dapat disalin—tidak seperti PDF yang hanya berisi gambar. + +## Pertanyaan yang Sering Diajukan + +**T: Apakah ini bekerja di macOS/Linux serta Windows?** +J: Tentu saja. Pemanggilan `Paths.get` mengabstraksi pemisah khusus OS, dan Aspose.HTML bersifat lintas‑platform. + +**T: Bisakah saya mengonversi bahasa markup lain (misalnya AsciiDoc) dengan API yang sama?** +J: Metode `Converter.convert` mendukung HTML, CSS, dan Markdown secara langsung. Untuk AsciiDoc Anda harus terlebih dahulu mengubahnya menjadi HTML (misalnya menggunakan AsciidoctorJ) lalu memberi HTML tersebut ke Aspose. + +**T: Apakah ada versi gratis Aspose.HTML?** +J: Aspose menawarkan lisensi evaluasi 30‑hari dengan fungsionalitas penuh. Untuk penggunaan produksi, lisensi komersial diperlukan. + +## Kesimpulan – Anda Telah Menguasai Membuat PDF dari Markdown di Java + +Kami telah membawa Anda dari pernyataan masalah—*bagaimana cara membuat PDF dari markdown?*—melalui solusi singkat yang dapat dijalankan, hingga ekstensi dunia nyata seperti pemrosesan batch dan layanan web. Dengan memanfaatkan metode `Converter.convert` milik Aspose.HTML, Anda dapat **mengonversi markdown ke pdf** hanya dengan beberapa baris kode, sambil tetap memiliki fleksibilitas untuk menyesuaikan ukuran halaman, header, footer, dan pengaturan performa. + +Langkah selanjutnya? Coba ganti `PdfSaveOptions` default dengan stylesheet kustom, bereksperimen dengan penyematan font, atau hubungkan konversi ke pipeline CI Anda sehingga setiap README otomatis menghasilkan artefak PDF. Langit adalah batasnya setelah Anda memiliki fondasi **java markdown to pdf** di tangan. + +Selamat coding, semoga PDF Anda selalu ter-render persis seperti yang Anda bayangkan! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/indonesian/java/conversion-html-to-various-image-formats/_index.md b/html/indonesian/java/conversion-html-to-various-image-formats/_index.md index 7251e034d..1217892a2 100644 --- a/html/indonesian/java/conversion-html-to-various-image-formats/_index.md +++ b/html/indonesian/java/conversion-html-to-various-image-formats/_index.md @@ -98,6 +98,7 @@ Pelajari cara mengkonversi HTML ke JPEG dengan Aspose.HTML untuk Java. Panduan l Pelajari cara mengkonversi HTML ke gambar PNG di Java dengan Aspose.HTML. Panduan komprehensif dengan instruksi langkah demi langkah. ### [Mengonversi HTML ke TIFF](./convert-html-to-tiff/) Pelajari cara mudah mengkonversi HTML ke TIFF menggunakan Aspose.HTML untuk Java. Panduan langkah demi langkah untuk penanganan dokumen yang efisien. +### [Cara mengatur DPI – Render HTML ke PNG dengan AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) ## Pertanyaan yang Sering Diajukan diff --git a/html/indonesian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/indonesian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..8748c7f3e --- /dev/null +++ b/html/indonesian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: cara mengatur dpi saat mengonversi URL ke PNG. Pelajari cara merender + HTML ke PNG, mengatur ukuran viewport, dan menyimpan HTML sebagai PNG menggunakan + Aspose.HTML di Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: id +og_description: cara mengatur dpi saat mengonversi URL ke PNG. Panduan langkah demi + langkah untuk merender HTML ke PNG, mengontrol ukuran viewport, dan menyimpan HTML + sebagai PNG menggunakan Aspose.HTML. +og_title: cara mengatur dpi – Render HTML ke PNG dengan AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: Cara mengatur DPI – Render HTML ke PNG dengan AsposeHTML +url: /id/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# cara mengatur dpi – Render HTML ke PNG dengan AsposeHTML + +Pernah bertanya-tanya **cara mengatur dpi** untuk gambar mirip screenshot yang dihasilkan dari halaman web? Mungkin Anda membutuhkan PNG 300 DPI untuk cetak, atau thumbnail beresolusi rendah untuk aplikasi seluler. Dalam kedua kasus, triknya adalah memberi tahu mesin render DPI logis yang Anda inginkan, lalu biarkan ia melakukan pekerjaan berat. + +Dalam tutorial ini kami akan mengambil URL langsung, merendernya ke file PNG, **mengatur ukuran viewport**, menyesuaikan DPI, dan akhirnya **menyimpan HTML sebagai PNG**—semua dengan Aspose.HTML untuk Java. Tanpa browser eksternal, tanpa alat baris perintah yang berantakan—hanya kode Java bersih yang dapat Anda masukkan ke proyek Maven atau Gradle apa pun. + +> **Pro tip:** Jika hanya menginginkan thumbnail cepat, Anda dapat mempertahankan DPI pada 96 DPI (default untuk kebanyakan layar). Untuk aset siap cetak, naikkan ke 300 DPI atau lebih tinggi. + +![contoh cara mengatur dpi](https://example.com/images/how-to-set-dpi.png "contoh cara mengatur dpi") + +## Apa yang Anda Butuhkan + +- **Java 17** (atau JDK terbaru lainnya). +- **Aspose.HTML for Java** 24.10 atau lebih baru. Anda dapat mengambilnya dari Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Koneksi internet untuk mengambil halaman target (contoh menggunakan `https://example.com/sample.html`). +- Izin menulis ke folder output. + +Itu saja—tanpa Selenium, tanpa Chrome headless. Aspose.HTML melakukan rendering di dalam proses, yang berarti Anda tetap berada di dalam JVM dan menghindari beban meluncurkan browser. + +## Langkah 1 – Muat Dokumen HTML dari URL + +Pertama kami membuat instance `HTMLDocument` yang menunjuk ke halaman yang ingin kami tangkap. Konstruktor secara otomatis mengunduh HTML, mem-parsenya, dan menyiapkan DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Mengapa ini penting:* Dengan memuat dokumen secara langsung, Anda melewatkan kebutuhan akan klien HTTP terpisah. Aspose.HTML menghormati pengalihan, cookie, dan bahkan otentikasi dasar jika Anda menyematkan kredensial dalam URL. + +## Langkah 2 – Bangun Sandbox dengan DPI dan Viewport yang Diinginkan + +Sebuah **sandbox** adalah cara Aspose.HTML meniru lingkungan browser. Di sini kami memberitahunya untuk berpura-pura menjadi layar 1280 × 720 dan, yang paling penting, kami mengatur **DPI perangkat**. Mengubah DPI mengubah kepadatan piksel gambar yang dirender tanpa mengubah ukuran logis. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Mengapa Anda mungkin menyesuaikan nilai-nilai ini:* +- **Ukuran viewport** mengontrol bagaimana media query CSS (`@media (max-width: …)`) berperilaku. +- **DPI perangkat** memengaruhi ukuran fisik gambar saat dicetak. Gambar 96 DPI terlihat baik di layar; gambar 300 DPI tetap tajam di kertas. + +Jika Anda membutuhkan thumbnail berbentuk kotak, cukup ubah `setViewportSize(500, 500)` dan pertahankan DPI rendah. + +## Langkah 3 – Pilih PNG sebagai Format Output + +Aspose.HTML mendukung beberapa format raster (PNG, JPEG, BMP, GIF). PNG bersifat loss‑less, sehingga cocok untuk screenshot di mana Anda menginginkan setiap piksel dipertahankan. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Anda juga dapat menyesuaikan tingkat kompresi (`pngOptions.setCompressionLevel(9)`) jika Anda khawatir tentang ukuran file. + +## Langkah 4 – Render dan Simpan Gambar + +Sekarang kami memberi tahu dokumen untuk **menyimpan** dirinya sebagai gambar. Metode `save` menerima jalur file dan opsi yang telah dikonfigurasi sebelumnya. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Saat program selesai, Anda akan menemukan file PNG di `YOUR_DIRECTORY/sandboxed.png`. Buka file tersebut—jika Anda mengatur DPI ke 300, metadata gambar akan mencerminkan hal itu, meskipun dimensi piksel tetap 1280 × 720. + +## Langkah 5 – Verifikasi DPI (Opsional tapi Berguna) + +Jika Anda ingin memeriksa kembali bahwa DPI benar-benar diterapkan, Anda dapat membaca metadata PNG dengan pustaka ringan seperti **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Anda akan melihat `300` (atau nilai yang Anda tetapkan) tercetak di konsol. Langkah ini tidak diperlukan untuk rendering, tetapi merupakan pemeriksaan cepat, terutama saat Anda menghasilkan aset untuk alur kerja cetak. + +## Pertanyaan Umum & Kasus Tepi + +### “Bagaimana jika halaman menggunakan JavaScript untuk memuat konten?” + +Aspose.HTML mengeksekusi **subset terbatas** dari JavaScript. Untuk kebanyakan situs statis, ini berfungsi langsung. Jika halaman sangat bergantung pada kerangka kerja sisi klien (React, Angular, Vue), Anda mungkin perlu melakukan pre‑render halaman atau menggunakan browser headless sebagai gantinya. Namun, pengaturan DPI tetap bekerja dengan cara yang sama setelah DOM siap. + +### “Bisakah saya merender PDF alih-alih PNG?” + +Tentu saja. Ganti `ImageSaveOptions` dengan `PdfSaveOptions` dan ubah ekstensi output menjadi `.pdf`. Pengaturan DPI tetap memengaruhi tampilan raster dari gambar yang disematkan. + +### “Bagaimana dengan screenshot resolusi tinggi untuk tampilan retina?” + +Cukup gandakan dimensi viewport sambil mempertahankan DPI pada 96 DPI, atau pertahankan viewport dan naikkan DPI ke 192. PNG yang dihasilkan akan berisi dua kali lebih banyak piksel, memberikan kesan retina yang tajam. + +### “Apakah saya perlu membersihkan sumber daya?” + +`HTMLDocument` mengimplementasikan `AutoCloseable`. Dalam aplikasi produksi, bungkuslah dalam blok try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Hal ini memastikan sumber daya native dilepaskan dengan cepat. + +## Contoh Lengkap yang Berfungsi (Siap Salin‑Tempel) + +Berikut adalah program lengkap yang siap dijalankan. Ganti `YOUR_DIRECTORY` dengan folder sebenarnya di mesin Anda. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Jalankan kelas tersebut, dan Anda akan mendapatkan PNG yang menghormati pengaturan **cara mengatur dpi** yang Anda tentukan. + +## Kesimpulan + +Kami telah membahas **cara mengatur dpi** ketika Anda **merender HTML ke PNG**, mencakup langkah **mengatur ukuran viewport**, dan menunjukkan cara **menyimpan HTML sebagai PNG** menggunakan Aspose.HTML untuk Java. Poin pentingnya adalah: + +- Gunakan **sandbox** untuk mengontrol DPI dan viewport. +- Pilih **ImageSaveOptions** yang tepat untuk output lossless. +- Verifikasi metadata DPI jika Anda perlu menjamin kualitas cetak. + +Dari sini Anda dapat bereksperimen dengan nilai DPI yang berbeda, viewport yang lebih besar, atau bahkan memproses batch daftar URL. Ingin mengonversi seluruh situs web menjadi thumbnail PNG? Cukup loop melalui array URL dan gunakan kembali konfigurasi sandbox yang sama. + +Selamat merender, semoga screenshot Anda selalu pixel‑perfect! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/indonesian/java/css-html-form-editing/_index.md b/html/indonesian/java/css-html-form-editing/_index.md index 402a3135d..ce5c74d3e 100644 --- a/html/indonesian/java/css-html-form-editing/_index.md +++ b/html/indonesian/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ Sekarang, mari kita beralih ke cara lain dan menjelajahi cara mengedit dan mengi Pelajari cara menggunakan Aspose.HTML untuk Java guna menerapkan teknik CSS tingkat lanjut, termasuk margin halaman khusus dan konten dinamis. Tutorial terperinci dan praktis untuk pengembang. ### [Pengeditan dan Pengiriman Formulir HTML dengan Aspose.HTML untuk Java](./html-form-editing/) Pelajari cara mengedit dan mengirimkan formulir HTML secara terprogram menggunakan Aspose.HTML untuk Java dalam panduan langkah demi langkah yang komprehensif ini. +### [Cara Mendapatkan Gaya di Java – Memuat HTML & Query Selector](./how-to-get-style-in-java-load-html-query-selector/) +Pelajari cara memuat dokumen HTML dan mengambil gaya menggunakan selector di Java dengan Aspose.HTML. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/indonesian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/indonesian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..e09995c87 --- /dev/null +++ b/html/indonesian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: id +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /id/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# cara mendapatkan style di Java – memuat HTML & query selector + +Pernah bertanya-tanya **cara mendapatkan style** sebuah elemen saat Anda mem-parsing HTML dengan Java? Mungkin Anda sedang membangun scraper, alat pengujian, atau hanya perlu memverifikasi petunjuk visual pada halaman yang dihasilkan. Kabar baiknya, Aspose.HTML membuat ini menjadi sangat mudah. Dalam tutorial ini kami akan membahas cara memuat dokumen HTML, menggunakan **contoh query selector**, dan akhirnya membaca **properti background-color** dari elemen `
`. Tidak ada sulap, hanya kode Java yang jelas yang dapat Anda salin‑tempel dan jalankan. + +## Apa yang Anda Butuhkan + +Sebelum kita mulai, pastikan Anda memiliki: + +* **Java 17** (atau JDK terbaru) – API ini bekerja dengan Java 8+ tetapi versi yang lebih baru memberikan kinerja yang lebih baik. +* **Aspose.HTML for Java** library – Anda dapat mengunduhnya dari Maven Central (`com.aspose:aspose-html:23.10` pada saat penulisan). +* Sebuah file HTML kecil (`input.html`) yang berisi setidaknya satu `
` dengan CSS background‑color yang diatur secara inline atau melalui stylesheet. + +Itu saja. Tidak ada kerangka kerja tambahan, tidak ada browser berat, hanya Java biasa dan Aspose.HTML. + +## Langkah 1: Muat Dokumen HTML + +Hal pertama yang harus Anda lakukan adalah **load html document** ke memori. Kelas `HTMLDocument` milik Aspose.HTML mengabstraksi penanganan sistem file dan memberi Anda DOM yang dapat Anda query. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Mengapa ini penting:** Memuat dokumen menciptakan pohon DOM yang telah diparse, yang menjadi dasar bagi evaluasi CSS atau JavaScript selanjutnya. Jika file tidak ditemukan, Aspose akan melempar `FileNotFoundException` yang deskriptif, jadi periksa kembali path-nya. + +### Tip Pro +Jika Anda mengambil HTML dari URL alih‑alih file, cukup berikan string URL ke konstruktor – Aspose menangani permintaan HTTP untuk Anda. + +## Langkah 2: Gunakan Contoh Query Selector + +Sekarang dokumen sudah berada di memori, mari **query selector example** untuk mengambil elemen `
` pertama. Metode `querySelector` meniru sintaks selector CSS yang sudah Anda kenal dari browser. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Mengapa ini penting:** `querySelector` mengembalikan node pertama yang cocok, yang sempurna ketika Anda hanya membutuhkan style satu elemen. Jika Anda memerlukan beberapa elemen, `querySelectorAll` mengembalikan `NodeList`. + +### Kasus khusus +Jika selector tidak menemukan apa‑apa, `divElement` akan bernilai `null`. Selalu periksa hal ini sebelum Anda mencoba membaca style: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Langkah 3: Dapatkan Gaya yang Dihitung + +Dengan elemen di tangan, langkah selanjutnya adalah **parse html java** cukup untuk menghitung nilai CSS akhir. Aspose.HTML melakukan pekerjaan berat: ia menyelesaikan cascade, inheritance, dan bahkan stylesheet eksternal. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Mengapa ini penting:** Gaya yang dihitung mencerminkan nilai tepat yang akan diterapkan browser setelah memproses semua aturan CSS. Ini lebih dapat diandalkan daripada membaca atribut `style` mentah, yang mungkin tidak lengkap. + +## Langkah 4: Ambil Properti background‑color + +Akhirnya, kami mengambil **background-color property** yang Anda butuhkan. Metode `getPropertyValue` mengembalikan nilai sebagai string (misalnya `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Apa yang akan Anda lihat:** Jika `
` Anda memiliki `background-color: #ff5733;` baik inline maupun melalui stylesheet, konsol akan menampilkan sesuatu seperti `Computed background‑color: rgb(255, 87, 51)`. + +### Jebakan umum +Ketika properti tidak didefinisikan, `getPropertyValue` mengembalikan string kosong. Itu menjadi sinyal untuk menggunakan nilai default atau memeriksa style elemen induknya. + +## Contoh Kerja Penuh + +Menggabungkan semuanya, berikut program lengkap yang siap dijalankan: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Output yang diharapkan (contoh):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Jika `
` tidak memiliki background color yang diatur, output akan berupa baris kosong – itu sinyal Anda untuk melihat style yang diwariskan. + +## Tips, Trik, dan Hal-hal yang Perlu Diwaspadai + +| Situasi | Apa yang Harus Dilakukan | +|-----------|------------| +| **Beberapa elemen `
`** | Gunakan `querySelectorAll("div")` dan iterasi melalui `NodeList`. | +| **File CSS eksternal** | Pastikan file HTML mereferensikannya dengan path yang benar; Aspose.HTML akan mengambilnya secara otomatis. | +| **Hanya atribut `style` inline** | `getComputedStyle` tetap berfungsi – ia menggabungkan style inline dengan nilai default. | +| **Kekhawatiran performa** | Muat dokumen sekali, gunakan kembali objek `HTMLDocument` jika Anda perlu query banyak elemen. | +| **Menjalankan di Android** | Aspose.HTML for Java mendukung Android, tetapi Anda harus menyertakan AAR khusus Android. | + +## Topik Terkait yang Mungkin Anda Jelajahi + +* **Parsing HTML dengan Jsoup vs. Aspose.HTML** – kapan memilih yang satu dibandingkan yang lain. +* **Mengekspor gaya yang dihitung ke JSON** – berguna untuk front‑end berbasis API. +* **Mengotomatiskan pembuatan screenshot** – gabungkan gaya yang dihitung dengan Aspose.PDF untuk pengujian regresi visual. + +--- + +### Kesimpulan + +Anda sekarang tahu **cara mendapatkan style** dari elemen apa pun ketika Anda **load html document** dengan Aspose.HTML, menjalankan **query selector example**, dan mengekstrak **background-color property**. Kode ini berdiri sendiri, berjalan pada JDK terbaru, dan menangani elemen yang hilang atau style yang tidak terdefinisi dengan elegan. Dari sini Anda dapat memperluas pendekatan untuk mengambil ukuran font, margin, atau bahkan nilai yang dihitung setelah eksekusi JavaScript (Aspose.HTML juga mendukung evaluasi skrip). + +Cobalah, ubah selector, dan lihat harta CSS lain yang dapat Anda temukan. Selamat coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/italian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/italian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..67fa2ed1f --- /dev/null +++ b/html/italian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: come impostare i dpi durante la conversione di un URL in PNG. Impara + a renderizzare HTML in PNG, impostare le dimensioni del viewport e salvare HTML + come PNG usando Aspose.HTML in Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: it +og_description: come impostare i dpi durante la conversione di un URL in PNG. Guida + passo‑passo per renderizzare HTML in PNG, controllare le dimensioni del viewport + e salvare HTML come PNG usando Aspose.HTML. +og_title: come impostare i DPI – Render HTML in PNG con AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: Come impostare i DPI – Render HTML in PNG con AsposeHTML +url: /it/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# come impostare dpi – Render HTML to PNG con AsposeHTML + +Ti sei mai chiesto **come impostare dpi** per un'immagine simile a uno screenshot generata da una pagina web? Forse ti serve un PNG a 300 DPI per la stampa, o una miniatura a bassa risoluzione per un'app mobile. In entrambi i casi, il trucco è dire al motore di rendering quale DPI logico desideri, quindi lasciarlo fare il lavoro pesante. + +In questo tutorial prenderemo un URL live, lo renderizzeremo in un file PNG, **imposteremo la dimensione del viewport**, regoleremo il DPI e infine **salveremo l'HTML come PNG** — tutto con Aspose.HTML per Java. Nessun browser esterno, nessuno strumento da riga di comando ingombrante — solo codice Java pulito che puoi inserire in qualsiasi progetto Maven o Gradle. + +> **Consiglio:** Se ti serve solo una miniatura veloce, puoi mantenere il DPI a 96 DPI (il valore predefinito per la maggior parte degli schermi). Per risorse pronte per la stampa, aumentalo a 300 DPI o più. + +![esempio di come impostare dpi](https://example.com/images/how-to-set-dpi.png "esempio di come impostare dpi") + +## Cosa ti serve + +- **Java 17** (o qualsiasi JDK recente). +- **Aspose.HTML for Java** 24.10 o più recente. Puoi scaricarlo da Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Una connessione internet per recuperare la pagina di destinazione (l'esempio utilizza `https://example.com/sample.html`). +- Permesso di scrittura sulla cartella di destinazione. + +Tutto qui — niente Selenium, niente Chrome headless. Aspose.HTML esegue il rendering in‑processo, il che significa che rimani all'interno della JVM ed eviti l'overhead di avviare un browser. + +## Passo 1 – Carica il documento HTML da un URL + +Per prima cosa creiamo un'istanza di `HTMLDocument` che punta alla pagina che vogliamo catturare. Il costruttore scarica automaticamente l'HTML, lo analizza e prepara il DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Perché è importante:* Caricando il documento direttamente, eviti la necessità di un client HTTP separato. Aspose.HTML rispetta i redirect, i cookie e anche l'autenticazione di base se inserisci le credenziali nell'URL. + +## Passo 2 – Crea un Sandbox con DPI e Viewport desiderati + +Un **sandbox** è il modo di Aspose.HTML di imitare un ambiente browser. Qui gli diciamo di fingere di essere uno schermo 1280 × 720 e, soprattutto, impostiamo il **DPI del dispositivo**. Cambiare il DPI modifica la densità di pixel dell'immagine renderizzata senza alterare le dimensioni logiche. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Perché potresti modificare questi valori:* +- **Viewport size** controlla il comportamento delle media query CSS (`@media (max-width: …)`). +- **Device DPI** influenza le dimensioni fisiche dell'immagine quando stampata. Un'immagine a 96 DPI appare bene sugli schermi; un'immagine a 300 DPI mantiene nitidezza sulla carta. + +Se ti serve una miniatura quadrata, basta cambiare `setViewportSize(500, 500)` e mantenere il DPI basso. + +## Passo 3 – Scegli PNG come formato di output + +Aspose.HTML supporta diversi formati raster (PNG, JPEG, BMP, GIF). PNG è loss‑less, il che lo rende perfetto per gli screenshot in cui vuoi preservare ogni pixel. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Puoi anche regolare il livello di compressione (`pngOptionsCompressionLevel(9)`) se ti preoccupi delle dimensioni del file. + +## Passo 4 – Renderizza e salva l'immagine + +Ora diciamo al documento di **salvare** se stesso come immagine. Il metodo `save` accetta un percorso file e le opzioni precedentemente configurate. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Quando il programma termina, troverai un file PNG in `YOUR_DIRECTORY/sandboxed.png`. Aprilo — se hai impostato il DPI a 300, i metadati dell'immagine lo rifletteranno, anche se le dimensioni in pixel rimangono 1280 × 720. + +## Passo 5 – Verifica il DPI (Opzionale ma utile) + +Se vuoi ricontrollare che il DPI sia stato davvero applicato, puoi leggere i metadati PNG con una libreria leggera come **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Dovresti vedere `300` (o qualunque valore tu abbia impostato) stampato sulla console. Questo pass non è necessario per il rendering, ma è un rapido controllo di coerenza, soprattutto quando generi risorse per un flusso di lavoro di stampa. + +## Domande comuni & casi limite + +### “E se la pagina usa JavaScript per caricare contenuti?” + +Aspose.HTML esegue un **sottoinsieme limitato** di JavaScript. Per la maggior parte dei siti statici funziona subito. Se la pagina dipende molto da framework lato client (React, Angular, Vue), potresti dover pre‑renderizzare la pagina o usare un browser headless. Tuttavia, l'impostazione del DPI funziona allo stesso modo una volta che il DOM è pronto. + +### “Posso renderizzare un PDF invece di PNG?” + +Assolutamente. Sostituisci `ImageSaveOptions` con `PdfSaveOptions` e cambia l'estensione di output in `.pdf`. L'impostazione del DPI influisce comunque sull'aspetto rasterizzato di eventuali immagini incorporate. + +### “E per gli screenshot ad alta risoluzione per display retina?” + +Basta raddoppiare le dimensioni del viewport mantenendo il DPI a 96 DPI, oppure mantenere il viewport e aumentare il DPI a 192. Il PNG risultante conterrà il doppio dei pixel, offrendoti quella nitidezza tipica dei display retina. + +### “Devo pulire le risorse?” + +`HTMLDocument` implementa `AutoCloseable`. In un'app di produzione, avvolgilo in un blocco try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## Esempio completo funzionante (pronto per copia‑incolla) + +Di seguito trovi il programma completo pronto per l'esecuzione. Sostituisci `YOUR_DIRECTORY` con una cartella reale sul tuo computer. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Esegui la classe e otterrai un PNG che rispetta l'impostazione **come impostare dpi** che hai specificato. + +## Conclusione + +Abbiamo illustrato **come impostare dpi** quando **renderizzi HTML in PNG**, coperto il passaggio **imposta la dimensione del viewport** e mostrato come **salvare l'HTML come PNG** usando Aspose.HTML per Java. I punti chiave sono: + +- Usa un **sandbox** per controllare DPI e viewport. +- Scegli le giuste **ImageSaveOptions** per un output lossless. +- Verifica i metadati DPI se devi garantire la qualità di stampa. + +Da qui puoi sperimentare con diversi valori DPI, viewport più grandi, o anche elaborare in batch un elenco di URL. Vuoi convertire un intero sito web in miniature PNG? Basta iterare su un array di URL e riutilizzare la stessa configurazione sandbox. + +Buon rendering, e che i tuoi screenshot siano sempre pixel‑perfect! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/italian/java/css-html-form-editing/_index.md b/html/italian/java/css-html-form-editing/_index.md index b6892964a..e8c1b6921 100644 --- a/html/italian/java/css-html-form-editing/_index.md +++ b/html/italian/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ Ora, cambiamo marcia ed esploriamo come modificare e inviare in modo efficace i Scopri come usare Aspose.HTML per Java per applicare tecniche CSS avanzate, tra cui margini di pagina personalizzati e contenuto dinamico. Un tutorial pratico e dettagliato per sviluppatori. ### [Modifica e invio di moduli HTML con Aspose.HTML per Java](./html-form-editing/) Scopri come modificare e inviare moduli HTML a livello di programmazione utilizzando Aspose.HTML per Java in questa guida completa passo dopo passo. +### [Come ottenere lo stile in Java – caricare HTML e query selector](./how-to-get-style-in-java-load-html-query-selector/) +Scopri come caricare un documento HTML in Java e recuperare gli stili usando i selettori di query con Aspose.HTML. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/italian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/italian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..e9b57c126 --- /dev/null +++ b/html/italian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: it +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /it/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# come ottenere lo stile in Java – caricare HTML e query selector + +Ti sei mai chiesto **come ottenere lo stile** di un elemento quando stai analizzando HTML con Java? Forse stai costruendo uno scraper, uno strumento di test, o semplicemente hai bisogno di verificare indizi visivi in una pagina generata. La buona notizia è che Aspose.HTML rende tutto questo un gioco da ragazzi. In questo tutorial vedremo come caricare un documento HTML, utilizzare un **esempio di query selector** e, infine, leggere la **proprietà background-color** di un elemento `
`. Nessuna magia, solo codice Java chiaro che puoi copiare‑incollare ed eseguire. + +## Cosa ti servirà + +Prima di immergerci, assicurati di avere: + +* **Java 17** (o qualsiasi JDK recente) – l'API funziona con Java 8+ ma le versioni più recenti offrono migliori prestazioni. +* Libreria **Aspose.HTML for Java** – puoi scaricarla da Maven Central (`com.aspose:aspose-html:23.10` al momento della stesura). +* Un piccolo file HTML (`input.html`) che contenga almeno un `
` con una proprietà CSS background‑color impostata inline o tramite un foglio di stile. + +Questo è tutto. Nessun framework aggiuntivo, nessun browser pesante, solo Java puro e Aspose.HTML. + +## Step 1: Carica il documento HTML + +La prima cosa da fare è **caricare il documento html** in memoria. La classe `HTMLDocument` di Aspose.HTML astrae la gestione del file‑system e ti fornisce un DOM su cui eseguire query. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Perché è importante:** Caricare il documento crea un albero DOM analizzato, che è la base per qualsiasi successiva valutazione di CSS o JavaScript. Se il file non viene trovato, Aspose lancia una `FileNotFoundException` descrittiva, quindi verifica il percorso. + +### Pro tip +Se stai recuperando HTML da un URL invece che da un file, passa semplicemente la stringa URL al costruttore – Aspose gestisce la richiesta HTTP per te. + +## Step 2: Usa un esempio di Query Selector + +Ora che il documento è in memoria, utilizziamo **un esempio di query selector** per ottenere il primo elemento `
`. Il metodo `querySelector` rispecchia la sintassi dei selettori CSS che già conosci dal browser. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Perché è importante:** `querySelector` restituisce il primo nodo corrispondente, perfetto quando ti serve lo stile di un solo elemento. Se ti servono più elementi, `querySelectorAll` restituisce un `NodeList`. + +### Caso limite +Se il selettore non corrisponde a nulla, `divElement` sarà `null`. Assicurati sempre di gestire questo caso prima di leggere gli stili: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Step 3: Ottieni lo stile calcolato + +Con l'elemento in mano, il passo successivo è **analizzare html java** a sufficienza per calcolare i valori CSS finali. Aspose.HTML fa il lavoro pesante: risolve la cascata, l'ereditarietà e anche i fogli di stile esterni. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Perché è importante:** Lo stile calcolato riflette i valori esatti che il browser applicherebbe dopo aver elaborato tutte le regole CSS. È più affidabile rispetto alla lettura dell'attributo `style` grezzo, che potrebbe essere incompleto. + +## Step 4: Recupera la proprietà background‑color + +Infine, estraiamo la **proprietà background-color** di cui abbiamo bisogno. Il metodo `getPropertyValue` restituisce il valore come stringa (es. `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Cosa vedrai:** Se il tuo `
` aveva `background-color: #ff5733;` inline o tramite un foglio di stile, la console stamperà qualcosa come `Computed background‑color: rgb(255, 87, 51)`. + +### Ostacolo comune +Quando la proprietà non è definita, `getPropertyValue` restituisce una stringa vuota. È un segnale per ricorrere a un valore predefinito o ispezionare gli stili del genitore dell'elemento. + +## Esempio completo funzionante + +Mettendo tutto insieme, ecco il programma completo, pronto da eseguire: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Output previsto (esempio):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Se il `
` non ha alcun colore di sfondo impostato, l'output sarà una riga vuota – è il tuo segnale per controllare gli stili ereditati. + +## Suggerimenti, trucchi e cose da tenere d'occhio + +| Situazione | Cosa fare | +|-----------|------------| +| **Più elementi `
`** | Usa `querySelectorAll("div")` e itera sul `NodeList`. | +| **File CSS esterni** | Assicurati che il file HTML li riferisca con percorsi corretti; Aspose.HTML li recupererà automaticamente. | +| **Solo attributo `style` inline** | `getComputedStyle` funziona comunque – unisce gli stili inline ai valori di default. | +| **Problemi di performance** | Carica il documento una sola volta, riutilizza l'oggetto `HTMLDocument` se devi interrogare molti elementi. | +| **Esecuzione su Android** | Aspose.HTML for Java supporta Android, ma dovrai includere l'AAR specifico per Android. | + +## Argomenti correlati che potresti esplorare + +* **Parsing HTML con Jsoup vs. Aspose.HTML** – quando scegliere l'uno rispetto all'altro. +* **Esportare gli stili calcolati in JSON** – utile per front‑end guidati da API. +* **Automatizzare la generazione di screenshot** – combina gli stili calcolati con Aspose.PDF per test di regressione visiva. + +--- + +### Conclusione + +Ora sai **come ottenere lo stile** di qualsiasi elemento quando **carichi un documento html** con Aspose.HTML, esegui un **esempio di query selector** e estrai la **proprietà background-color**. Il codice è autonomo, funziona su qualsiasi JDK recente e gestisce elegantemente elementi mancanti o stili non definiti. Da qui puoi estendere l'approccio per recuperare dimensioni dei font, margini o anche valori calcolati dopo l'esecuzione di JavaScript (Aspose.HTML supporta anche la valutazione di script). + +Provalo, modifica il selettore e scopri quali altri tesori CSS puoi svelare. Buon coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/japanese/java/conversion-html-to-various-image-formats/_index.md b/html/japanese/java/conversion-html-to-various-image-formats/_index.md index 5ac43aed7..baa60d128 100644 --- a/html/japanese/java/conversion-html-to-various-image-formats/_index.md +++ b/html/japanese/java/conversion-html-to-various-image-formats/_index.md @@ -96,6 +96,8 @@ Aspose.HTML を使用して Java で HTML を PNG 画像に変換する方法を ### [HTML を TIFF に変換](./convert-html-to-tiff/) Aspose.HTML for Java を使用して HTML を TIFF に簡単に変換する方法を学びます。効率的なドキュメント処理のためのステップバイステップガイドです。 +### [DPI を設定する方法 – AsposeHTML で HTML を PNG にレンダリング](./how-to-set-dpi-render-html-to-png-with-asposehtml/) + ## よくある質問 **Q: 追加の画像ライブラリなしで Java で HTML を PNG に変換できますか?** diff --git a/html/japanese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/japanese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..89d4d9b61 --- /dev/null +++ b/html/japanese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: URL を PNG に変換するときに DPI を設定する方法。Aspose.HTML を使用して Java で HTML を PNG にレンダリングし、ビューポートサイズを設定し、HTML + を PNG として保存する方法を学びます。 +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: ja +og_description: URL を PNG に変換するときに DPI を設定する方法。HTML を PNG にレンダリングし、ビューポートサイズを制御し、Aspose.HTML + を使用して HTML を PNG として保存するステップバイステップガイド。 +og_title: DPIの設定方法 – AsposeHTMLでHTMLをPNGにレンダリング +tags: +- AsposeHTML +- Java +- image rendering +title: dpi の設定方法 – AsposeHTML で HTML を PNG にレンダリング +url: /ja/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# DPI の設定方法 – Aspose.HTML を使用した HTML の PNG へのレンダリング + +Web ページから生成されたスクリーンショットのような画像の **DPI の設定方法** を考えたことはありますか?印刷用に 300 DPI の PNG が必要な場合や、モバイルアプリ用の低解像度サムネイルが必要な場合があります。どちらの場合でも、レンダリングエンジンに論理 DPI を指定し、残りの処理を任せるのがコツです。 + +このチュートリアルでは、実際の URL を取得し、PNG ファイルにレンダリングし、**ビューポートサイズを設定**し、DPI を調整し、最後に **HTML を PNG として保存** します—すべて Aspose.HTML for Java を使用します。外部ブラウザや面倒なコマンドラインツールは不要で、Maven や Gradle プロジェクトにそのまま組み込めるシンプルな Java コードだけです。 + +> **プロのコツ:** 手軽なサムネイルだけが必要な場合は、DPI を 96 DPI(ほとんどの画面のデフォルト)に保って構いません。印刷用のアセットの場合は、300 DPI 以上に上げてください。 + +![DPI 設定例](https://example.com/images/how-to-set-dpi.png "DPI 設定例") + +## 必要なもの + +- **Java 17**(または最近の JDK)。 +- **Aspose.HTML for Java** 24.10 以上。Maven Central から取得できます: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- ターゲットページを取得するためのインターネット接続(例では `https://example.com/sample.html` を使用)。 +- 出力フォルダーへの書き込み権限。 + +以上です—Selenium もヘッドレス Chrome も不要。Aspose.HTML はプロセス内でレンダリングを行うため、JVM 内に留まり、ブラウザ起動のオーバーヘッドを回避できます。 + +## ステップ 1 – URL から HTML ドキュメントをロード + +まず、取得したいページを指す `HTMLDocument` インスタンスを作成します。コンストラクタは自動的に HTML をダウンロードし、解析し、DOM を準備します。 + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*この重要性:* ドキュメントを直接ロードすることで、別途 HTTP クライアントを使用する必要がなくなります。Aspose.HTML はリダイレクト、クッキー、URL に埋め込んだ基本認証もサポートします。 + +## ステップ 2 – 任意の DPI とビューポートでサンドボックスを構築 + +**サンドボックス** は Aspose.HTML がブラウザ環境を模倣する仕組みです。ここでは、1280 × 720 の画面として振る舞うよう指示し、重要な **デバイス DPI** を設定します。DPI を変更すると、論理サイズは変わらずにレンダリング画像のピクセル密度が変わります。 + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*これらの値を調整する理由:* +- **ビューポートサイズ** は CSS メディアクエリ(`@media (max-width: …)`)の挙動を制御します。 +- **デバイス DPI** は印刷時の画像の実際のサイズに影響します。96 DPI の画像は画面上で問題ありませんが、300 DPI の画像は紙上で鮮明さを保ちます。 + +正方形のサムネイルが必要な場合は、`setViewportSize(500, 500)` に変更し、DPI は低めに保ちます。 + +## ステップ 3 – 出力形式として PNG を選択 + +Aspose.HTML は複数のラスタ形式(PNG、JPEG、BMP、GIF)をサポートしています。PNG はロスレスで、すべてのピクセルを保持したいスクリーンショットに最適です。 + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +ファイルサイズが気になる場合は、圧縮レベル(`pngOptions.setCompressionLevel(9)`)を調整することもできます。 + +## ステップ 4 – 画像をレンダリングして保存 + +ここで、ドキュメントに画像として **保存** させます。`save` メソッドはファイルパスと先ほど設定したオプションを受け取ります。 + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +プログラムが終了すると、`YOUR_DIRECTORY/sandboxed.png` に PNG ファイルが生成されます。開いてみてください—DPI を 300 に設定していれば、ピクセルサイズは 1280 × 720 のままメタデータにその DPI が記録されています。 + +## ステップ 5 – DPI を確認する(任意だが便利) + +DPI が正しく適用されたか二重チェックしたい場合は、軽量ライブラリ **metadata‑extractor** で PNG のメタデータを読み取れます。 + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +コンソールに `300`(設定した値)が表示されるはずです。この手順はレンダリングに必須ではありませんが、特に印刷ワークフロー向けのアセットを生成する際の簡易的な確認として便利です。 + +## よくある質問とエッジケース + +### 「ページが JavaScript でコンテンツをロードする場合は?」 + +Aspose.HTML は **限定的なサブセット** の JavaScript を実行します。ほとんどの静的サイトではそのまま機能します。ページがクライアント側フレームワーク(React、Angular、Vue)に大きく依存している場合は、ページを事前にレンダリングするか、ヘッドレスブラウザを使用する必要があります。ただし、DOM が準備できれば DPI の設定は同様に機能します。 + +### 「PNG の代わりに PDF をレンダリングできますか?」 + +もちろんです。`ImageSaveOptions` を `PdfSaveOptions` に置き換え、出力拡張子を `.pdf` に変更します。DPI 設定は埋め込まれた画像のラスタ化された外観にも影響します。 + +### 「Retina ディスプレイ向けの高解像度スクリーンショットはどうすれば?」 + +ビューポートのサイズを 2 倍にしつつ DPI を 96 DPI のままにするか、ビューポートはそのままで DPI を 192 に上げます。生成される PNG はピクセル数が 2 倍になり、Retina ディスプレイ向けの鮮明さが得られます。 + +### 「リソースのクリーンアップは必要ですか?」 + +`HTMLDocument` は `AutoCloseable` を実装しています。本番アプリでは、try‑with‑resources ブロックでラップしてください: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +これにより、ネイティブリソースが速やかに解放されます。 + +## 完全動作サンプル(コピー&ペースト可能) + +以下に、完全な実行可能プログラムを示します。`YOUR_DIRECTORY` を実際のフォルダーに置き換えてください。 + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +クラスを実行すると、指定した **DPI の設定** を反映した PNG が生成されます。 + +## 結論 + +本稿では、**HTML を PNG にレンダリングする際の DPI の設定方法** を解説し、**ビューポートサイズの設定** 手順を取り上げ、Aspose.HTML for Java を使用した **HTML の PNG 保存** 方法を示しました。主なポイントは以下の通りです。 + +- **サンドボックス** を使用して DPI とビューポートを制御する。 +- ロスレス出力には適切な **ImageSaveOptions** を選択する。 +- 印刷品質を保証する必要がある場合は DPI メタデータを確認する。 + +ここからは、さまざまな DPI 値や大きなビューポート、さらには URL のリストをバッチ処理することも試せます。ウェブサイト全体を PNG サムネイルに変換したい場合は、URL 配列をループし、同じサンドボックス設定を再利用すれば完了です。 + +レンダリングを楽しんで、スクリーンショットが常にピクセルパーフェクトでありますように! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/japanese/java/css-html-form-editing/_index.md b/html/japanese/java/css-html-form-editing/_index.md index 5a4b827f9..3831ff9c1 100644 --- a/html/japanese/java/css-html-form-editing/_index.md +++ b/html/japanese/java/css-html-form-editing/_index.md @@ -30,9 +30,11 @@ Web 開発に取り組む場合、CSS および HTML フォームを習得する Aspose.HTML for Java を使用して、カスタム ページ マージンや動的コンテンツなどの高度な CSS テクニックを適用する方法を学びます。開発者向けの詳細な実践的なチュートリアルです。 ### [Aspose.HTML for Java を使用した HTML フォームの編集と送信](./html-form-editing/) この包括的なステップバイステップ ガイドでは、Aspose.HTML for Java を使用して HTML フォームをプログラムで編集および送信する方法を学習します。 +### [Javaでスタイルを取得する方法 – HTMLのロードとクエリセレクタ](./how-to-get-style-in-java-load-html-query-selector/) +JavaでHTMLをロードし、クエリセレクタでスタイル情報を取得する手順を解説します。 {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/japanese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/japanese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..cb5eae07a --- /dev/null +++ b/html/japanese/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: ja +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /ja/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Java でスタイルを取得する方法 – HTML の読み込みとクエリセレクタ + +HTML を Java でパースするときに、要素の **スタイルを取得する方法** が気になったことはありませんか? スクレイパーやテストツールを作っている場合、あるいは生成されたページの視覚的な手がかりを確認したいだけの場合でも、Aspose.HTML があれば簡単に実現できます。このチュートリアルでは、HTML ドキュメントの読み込み、**クエリセレクタの例** の使用、そして `
` 要素の **background-color プロパティ** の取得までを順を追って解説します。魔法はありません、コピー&ペーストしてすぐに実行できるシンプルな Java コードです。 + +## 必要な環境 + +始める前に以下を用意してください。 + +* **Java 17**(または最近の JDK) – API は Java 8 以降で動作しますが、最新バージョンの方がパフォーマンスが向上します。 +* **Aspose.HTML for Java** ライブラリ – Maven Central から取得できます(執筆時点では `com.aspose:aspose-html:23.10`)。 +* 小さな HTML ファイル(`input.html`)で、インラインまたは外部スタイルシートで CSS の background‑color が設定された `
` が最低1つ含まれていること。 + +以上です。余計なフレームワークや重いブラウザは不要、純粋な Java と Aspose.HTML だけで完結します。 + +## Step 1: HTML ドキュメントの読み込み + +最初に **HTML ドキュメントをメモリにロード** します。Aspose.HTML の `HTMLDocument` クラスはファイルシステムの扱いを抽象化し、クエリ可能な DOM を提供します。 + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **なぜ重要か:** ドキュメントをロードすると解析済みの DOM ツリーが生成され、以降の CSS や JavaScript の評価の基盤となります。ファイルが見つからない場合は Aspose が詳細な `FileNotFoundException` をスローするので、パスを再確認してください。 + +### プロ・ティップ +URL から HTML を取得したい場合は、ファイルの代わりに URL 文字列をコンストラクタに渡すだけです。Aspose が HTTP リクエストを内部で処理します。 + +## Step 2: クエリセレクタの例を使用 + +ドキュメントがメモリ上にあるので、**クエリセレクタの例** を使って最初の `
` 要素を取得しましょう。`querySelector` メソッドはブラウザで慣れ親しんだ CSS セレクタ構文と同じです。 + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **なぜ重要か:** `querySelector` は最初にマッチしたノードを返すため、単一要素のスタイルだけが必要なときに最適です。複数要素が必要な場合は `querySelectorAll` が `NodeList` を返します。 + +### エッジケース +セレクタが何もマッチしなかった場合、`divElement` は `null` になります。スタイルを読む前に必ず null チェックを行いましょう。 + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Step 3: 計算済みスタイルの取得 + +要素が取得できたら、次は **HTML を Java で解析** して最終的な CSS 値を計算します。Aspose.HTML がカスケード、継承、外部スタイルシートの解決をすべて行ってくれます。 + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **なぜ重要か:** 計算済みスタイルは、ブラウザがすべての CSS ルールを適用した後に実際に使用する値を正確に反映します。生の `style` 属性を読むよりも信頼性が高いです。 + +## Step 4: background‑color プロパティの取得 + +最後に、**background-color プロパティ** を取得します。`getPropertyValue` メソッドは値を文字列で返します(例: `rgba(255, 0, 0, 1)`)。 + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **期待される出力:** `
` にインラインまたは外部スタイルシートで `background-color: #ff5733;` が設定されていれば、コンソールに `Computed background‑color: rgb(255, 87, 51)` のように表示されます。 + +### よくある落とし穴 +プロパティが未定義の場合、`getPropertyValue` は空文字列を返します。これはデフォルト値にフォールバックするか、親要素のスタイルを調べるサインです。 + +## 完全動作サンプル + +すべてを組み合わせた、実行可能な完全プログラムは以下の通りです。 + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**期待出力(例):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +`
` に背景色が設定されていない場合は空行が出力されます。これは継承されたスタイルを確認すべきサインです。 + +## ヒント、コツ、注意点 + +| シチュエーション | 対応策 | +|-----------|------------| +| **複数の `
` 要素** | `querySelectorAll("div")` を使用し、`NodeList` をイテレートします。 | +| **外部 CSS ファイル** | HTML が正しいパスで外部 CSS を参照していることを確認してください。Aspose.HTML が自動的に取得します。 | +| **インライン `style` 属性のみ** | `getComputedStyle` はインラインスタイルとデフォルトをマージしてくれます。 | +| **パフォーマンスの懸念** | ドキュメントは一度だけロードし、複数要素をクエリする場合は同じ `HTMLDocument` オブジェクトを再利用します。 | +| **Android 上での実行** | Aspose.HTML for Java は Android をサポートしていますが、Android 用 AAR を追加で含める必要があります。 | + +## 関連トピック + +* **Jsoup と Aspose.HTML の HTML パース比較** – どちらを選ぶべきか。 +* **計算済みスタイルを JSON にエクスポート** – API 主導のフロントエンドに便利。 +* **スクリーンショット自動生成** – 計算済みスタイルと Aspose.PDF を組み合わせてビジュアルリグレッションテストを実施。 + +--- + +### 結論 + +これで **HTML ドキュメントを読み込んで** Aspose.HTML を使い、**クエリセレクタの例** を実行し、**background-color プロパティ** を抽出する方法が分かりました。コードは自己完結型で、最新の JDK 上で動作し、要素が見つからない場合やスタイルが未定義の場合にも安全に対処できます。ここからはフォントサイズやマージン、さらには JavaScript 実行後の計算値取得(Aspose.HTML はスクリプト評価もサポート)へと応用範囲を広げられます。 + +ぜひ試してみて、セレクタを調整しながら他の CSS の宝石を見つけてください。ハッピーコーディング! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/korean/java/conversion-html-to-various-image-formats/_index.md b/html/korean/java/conversion-html-to-various-image-formats/_index.md index a5077eac1..d9574f148 100644 --- a/html/korean/java/conversion-html-to-various-image-formats/_index.md +++ b/html/korean/java/conversion-html-to-various-image-formats/_index.md @@ -94,6 +94,8 @@ Aspose.HTML를 사용해 Java에서 HTML을 GIF로 변환하는 방법을 배웁 Aspose.HTML for Java를 사용해 HTML을 JPEG로 변환하는 방법을 배웁니다. 원활한 문서 처리를 위한 단계별 가이드입니다. ### [HTML을 PNG로 변환](./convert-html-to-png/) Aspose.HTML를 사용해 Java에서 HTML을 PNG 이미지로 변환하는 방법을 배웁니다. 단계별 지침이 포함된 포괄적인 가이드입니다. +### [dpi 설정 – AsposeHTML로 HTML을 PNG로 렌더링](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +AsposeHTML를 사용해 PNG 이미지의 DPI를 설정하는 방법을 단계별로 안내합니다. ### [HTML을 TIFF로 변환](./convert-html-to-tiff/) Aspose.HTML for Java를 사용해 HTML을 TIFF로 쉽게 변환하는 방법을 배웁니다. 효율적인 문서 처리를 위한 단계별 가이드입니다. diff --git a/html/korean/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/korean/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..675d69ea9 --- /dev/null +++ b/html/korean/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: URL을 PNG로 변환할 때 DPI를 설정하는 방법. Aspose.HTML을 사용하여 Java에서 HTML을 PNG로 렌더링하고, + 뷰포트 크기를 설정하며, HTML을 PNG로 저장하는 방법을 배웁니다. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: ko +og_description: URL을 PNG로 변환할 때 DPI를 설정하는 방법. HTML을 PNG로 렌더링하고, 뷰포트 크기를 제어하며, Aspose.HTML을 + 사용하여 HTML을 PNG로 저장하는 단계별 가이드. +og_title: dpi 설정 방법 – AsposeHTML로 HTML을 PNG로 렌더링 +tags: +- AsposeHTML +- Java +- image rendering +title: dpi 설정 방법 – AsposeHTML로 HTML을 PNG로 렌더링 +url: /ko/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# DPI 설정 방법 – AsposeHTML로 HTML을 PNG로 렌더링 + +웹 페이지에서 생성된 스크린샷과 같은 이미지의 **DPI 설정 방법**이 궁금하셨나요? 인쇄용 300 DPI PNG가 필요할 수도 있고, 모바일 앱용 저해상도 썸네일이 필요할 수도 있습니다. 어느 경우든, 렌더링 엔진에 원하는 논리 DPI를 알려주고 나머지는 엔진이 처리하도록 하면 됩니다. + +이 튜토리얼에서는 실시간 URL을 가져와 PNG 파일로 렌더링하고, **뷰포트 크기**를 설정한 뒤 DPI를 조정하고, 마지막으로 **HTML을 PNG로 저장**하는 과정을 Aspose.HTML for Java로 진행합니다. 외부 브라우저나 복잡한 커맨드라인 도구 없이, Maven이나 Gradle 프로젝트에 바로 넣을 수 있는 깔끔한 Java 코드만 있으면 됩니다. + +> **Pro tip:** 빠른 썸네일만 필요하다면 DPI를 96 DPI(대부분 화면의 기본값)로 유지하면 됩니다. 인쇄용 자산이라면 300 DPI 이상으로 올려 주세요. + +![DPI 설정 예시](https://example.com/images/how-to-set-dpi.png "DPI 설정 예시") + +## 필요 사항 + +- **Java 17** (또는 최신 JDK). +- **Aspose.HTML for Java** 24.10 이상. Maven Central에서 받아 사용할 수 있습니다: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- 대상 페이지를 가져오기 위한 인터넷 연결(`https://example.com/sample.html` 예시 사용). +- 출력 폴더에 대한 쓰기 권한. + +그게 전부입니다—Selenium도, 헤드리스 Chrome도 필요 없습니다. Aspose.HTML은 프로세스 내에서 렌더링을 수행하므로 JVM 안에서 작업을 마칠 수 있어 브라우저 실행 오버헤드를 피할 수 있습니다. + +## 단계 1 – URL에서 HTML 문서 로드 + +먼저 캡처하려는 페이지를 가리키는 `HTMLDocument` 인스턴스를 생성합니다. 생성자는 HTML을 자동으로 다운로드하고, 파싱하며, DOM을 준비합니다. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Why this matters:* 문서를 직접 로드함으로써 별도의 HTTP 클라이언트를 사용할 필요가 없습니다. Aspose.HTML은 리다이렉트, 쿠키, 그리고 URL에 자격 증명을 포함했을 경우 기본 인증까지도 지원합니다. + +## 단계 2 – 원하는 DPI와 뷰포트를 사용해 샌드박스 구축 + +**sandbox**는 Aspose.HTML이 브라우저 환경을 흉내 내는 방식입니다. 여기서는 화면을 1280 × 720으로 가정하고, 중요한 **device DPI**를 설정합니다. DPI를 바꾸면 논리적 크기는 그대로 두고 렌더링된 이미지의 픽셀 밀도가 변합니다. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Why you might tweak these values:* +- **Viewport size**는 CSS 미디어 쿼리(`@media (max-width: …)`)가 동작하는 방식을 제어합니다. +- **Device DPI**는 인쇄 시 이미지의 물리적 크기에 영향을 줍니다. 96 DPI 이미지는 화면에서 잘 보이지만, 300 DPI 이미지는 인쇄물에서 선명함을 유지합니다. + +정사각형 썸네일이 필요하면 `setViewportSize(500, 500)`으로 바꾸고 DPI는 낮게 유지하면 됩니다. + +## 단계 3 – PNG를 출력 포맷으로 선택 + +Aspose.HTML은 여러 래스터 포맷(PNG, JPEG, BMP, GIF)을 지원합니다. PNG는 손실이 없으므로 모든 픽셀을 보존해야 하는 스크린샷에 최적입니다. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +파일 크기가 걱정된다면 `pngOptions.setCompressionLevel(9)`와 같이 압축 레벨을 조정할 수 있습니다. + +## 단계 4 – 이미지 렌더링 및 저장 + +이제 문서에게 **이미지로 저장**하도록 지시합니다. `save` 메서드는 파일 경로와 앞서 설정한 옵션을 인수로 받습니다. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +프로그램이 종료되면 `YOUR_DIRECTORY/sandboxed.png`에 PNG 파일이 생성됩니다. DPI를 300으로 설정했다면 픽셀 크기(1280 × 720)는 그대로이지만 메타데이터에 300 DPI가 기록됩니다. + +## 단계 5 – DPI 확인 (선택 사항이지만 유용) + +DPI가 실제로 적용됐는지 다시 확인하고 싶다면 **metadata-extractor** 같은 경량 라이브러리로 PNG 메타데이터를 읽어볼 수 있습니다: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +콘솔에 `300`(또는 설정한 값)이 출력되는 것을 확인할 수 있습니다. 이 단계는 렌더링에 필수는 아니지만, 인쇄 워크플로우용 자산을 만들 때 빠른 검증 수단이 됩니다. + +## 일반적인 질문 및 예외 상황 + +### “페이지가 JavaScript로 콘텐츠를 로드한다면 어떻게 하나요?” + +Aspose.HTML은 **제한된 JavaScript 하위 집합**을 실행합니다. 대부분 정적 사이트에서는 바로 동작합니다. 페이지가 React, Angular, Vue와 같은 클라이언트‑사이드 프레임워크에 크게 의존한다면 사전 렌더링하거나 헤드리스 브라우저를 사용하는 것이 좋습니다. 다만 DOM이 준비된 뒤에는 DPI 설정 방식이 동일합니다. + +### “PNG 대신 PDF로 렌더링할 수 있나요?” + +가능합니다. `ImageSaveOptions`를 `PdfSaveOptions`로 교체하고 파일 확장자를 `.pdf`로 바꾸면 됩니다. DPI 설정은 여전히 임베드된 이미지의 래스터화된 모습에 영향을 줍니다. + +### “레티나 디스플레이용 고해상도 스크린샷은 어떻게 만들죠?” + +뷰포트 크기를 두 배로 늘리면서 DPI를 96 DPI로 유지하거나, 뷰포트를 유지한 채 DPI를 192로 올리면 됩니다. 이렇게 하면 픽셀 수가 두 배가 되어 레티나 화면에서도 선명하게 보입니다. + +### “리소스를 정리해야 하나요?” + +`HTMLDocument`는 `AutoCloseable`을 구현합니다. 프로덕션 환경에서는 try‑with‑resources 블록으로 감싸는 것이 좋습니다: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +이렇게 하면 네이티브 리소스가 즉시 해제됩니다. + +## 전체 작업 예제 (복사‑붙여넣기 가능) + +아래는 완전한 실행 가능한 프로그램 예제입니다. `YOUR_DIRECTORY`를 실제 폴더 경로로 바꾸세요. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +클래스를 실행하면 **DPI 설정 방법**에 맞춰 PNG가 생성됩니다. + +## 결론 + +우리는 **HTML을 PNG로 렌더링할 때 DPI를 설정하는 방법**을 살펴보고, **뷰포트 크기 설정** 단계와 **HTML을 PNG로 저장**하는 방법을 Aspose.HTML for Java를 사용해 구현했습니다. 핵심 포인트는 다음과 같습니다: + +- DPI와 뷰포트를 제어하려면 **sandbox**를 사용하세요. +- 무손실 출력을 위해 적절한 **ImageSaveOptions**를 선택하세요. +- 인쇄 품질을 보장해야 한다면 DPI 메타데이터를 검증하세요. + +이제 다양한 DPI 값, 더 큰 뷰포트, 혹은 URL 목록을 일괄 처리하는 등 여러 시나리오를 실험해 볼 수 있습니다. 전체 웹사이트를 PNG 썸네일로 변환하고 싶다면 URL 배열을 순회하면서 동일한 sandbox 구성을 재사용하면 됩니다. + +즐거운 렌더링 되세요, 그리고 스크린샷이 언제나 픽셀 완벽하게 나오길 바랍니다! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/korean/java/css-html-form-editing/_index.md b/html/korean/java/css-html-form-editing/_index.md index a6f5a6124..f5887d4d9 100644 --- a/html/korean/java/css-html-form-editing/_index.md +++ b/html/korean/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ url: /ko/java/css-html-form-editing/ Aspose.HTML for Java를 사용하여 사용자 정의 페이지 여백 및 동적 콘텐츠를 포함한 고급 CSS 기술을 적용하는 방법을 알아보세요. 개발자를 위한 자세하고 실용적인 튜토리얼입니다. ### [Aspose.HTML for Java를 사용한 HTML 양식 편집 및 제출](./html-form-editing/) 이 포괄적인 단계별 가이드를 통해 Java용 Aspose.HTML을 사용하여 HTML 양식을 프로그래밍 방식으로 편집하고 제출하는 방법을 알아보세요. +### [Java에서 스타일 가져오기 – HTML 로드 및 쿼리 선택자](./how-to-get-style-in-java-load-html-query-selector/) +Java용 Aspose.HTML을 사용해 HTML을 로드하고 쿼리 선택자로 스타일을 추출하는 방법을 배웁니다. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/korean/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/korean/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..29b0e8e44 --- /dev/null +++ b/html/korean/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: Java에서 스타일을 가져오는 방법 – HTML 문서를 로드하고, 쿼리 셀렉터 예제를 사용하며, Aspose.HTML로 background-color + 속성을 읽는 방법을 배웁니다. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: ko +og_description: Java에서 스타일을 가져오는 방법 – HTML 문서를 로드하고, query selector 예제를 실행하며, background-color + 속성을 가져오는 단계별 가이드. +og_title: Java에서 스타일 가져오기 – HTML 로드 및 쿼리 셀렉터 +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: Java에서 스타일을 가져오는 방법 – HTML 로드 및 쿼리 셀렉터 +url: /ko/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Java에서 스타일 가져오기 – HTML 로드 및 쿼리 셀렉터 사용 + +HTML을 Java로 파싱할 때 **요소의 스타일을 가져오는 방법**이 궁금하셨나요? 스크래퍼를 만들거나, 테스트 도구를 개발하거나, 생성된 페이지에서 시각적 힌트를 확인해야 할 때가 있을 겁니다. 좋은 소식은 Aspose.HTML을 사용하면 이 작업이 아주 쉬워진다는 것입니다. 이번 튜토리얼에서는 HTML 문서를 로드하고, **쿼리 셀렉터 예제**를 사용한 뒤, `
` 요소의 **background-color 속성**을 읽는 과정을 단계별로 살펴보겠습니다. 마법이 아니라 복사‑붙여넣기만 하면 바로 실행할 수 있는 명확한 Java 코드입니다. + +## 준비물 + +시작하기 전에 아래 항목을 준비하세요: + +* **Java 17** (또는 최신 JDK) – API는 Java 8+에서도 동작하지만 최신 버전이 더 나은 성능을 제공합니다. +* **Aspose.HTML for Java** 라이브러리 – 현재(`23.10`) Maven Central에서 `com.aspose:aspose-html:23.10`으로 가져올 수 있습니다. +* 최소 하나의 `
`가 포함된 작은 HTML 파일(`input.html`) – CSS `background-color`가 인라인이든 외부 스타일시트이든 설정되어 있어야 합니다. + +이것만 있으면 됩니다. 별도의 프레임워크나 무거운 브라우저는 필요 없으며, 순수 Java와 Aspose.HTML만 있으면 됩니다. + +## Step 1: HTML 문서 로드 + +먼저 **HTML 문서를 메모리로 로드**해야 합니다. Aspose.HTML의 `HTMLDocument` 클래스는 파일 시스템 처리를 추상화하고, 쿼리할 수 있는 DOM을 제공합니다. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **왜 중요한가:** 문서를 로드하면 파싱된 DOM 트리가 생성되며, 이는 이후 CSS나 JavaScript 평가의 기반이 됩니다. 파일을 찾을 수 없으면 Aspose가 상세한 `FileNotFoundException`을 발생시키니 경로를 반드시 확인하세요. + +### Pro tip +HTML을 파일이 아니라 URL에서 가져오는 경우, 생성자에 URL 문자열만 전달하면 됩니다 – Aspose가 HTTP 요청을 자동으로 처리합니다. + +## Step 2: 쿼리 셀렉터 예제 사용 + +문서가 메모리에 로드되었으니 **쿼리 셀렉터 예제**를 사용해 첫 번째 `
` 요소를 잡아봅시다. `querySelector` 메서드는 브라우저에서 익숙한 CSS 선택자 문법을 그대로 사용합니다. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **왜 중요한가:** `querySelector`는 첫 번째 매칭 노드를 반환하므로 단일 요소의 스타일만 필요할 때 적합합니다. 여러 요소가 필요하면 `querySelectorAll`이 `NodeList`를 반환합니다. + +### Edge case +선택자가 아무 것도 매칭하지 않으면 `divElement`는 `null`이 됩니다. 스타일을 읽기 전에 반드시 null 체크를 해야 합니다: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Step 3: 계산된 스타일 가져오기 + +요소를 확보했으니 이제 **HTML을 파싱**하여 최종 CSS 값을 계산합니다. Aspose.HTML이 무거운 작업을 대신해 줍니다: cascade, inheritance, 외부 스타일시트까지 모두 해결합니다. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **왜 중요한가:** 계산된 스타일은 브라우저가 모든 CSS 규칙을 처리한 뒤 적용하는 정확한 값을 반영합니다. 원시 `style` 속성을 읽는 것보다 신뢰성이 높습니다. + +## Step 4: background‑color 속성 가져오기 + +마지막으로 **background-color 속성**을 추출합니다. `getPropertyValue` 메서드는 값을 문자열로 반환합니다(예: `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **출력 예시:** `
`에 `background-color: #ff5733;`이 인라인이든 스타일시트를 통해 적용되었든, 콘솔에는 `Computed background‑color: rgb(255, 87, 51)`와 같은 결과가 표시됩니다. + +### Common pitfall +속성이 정의되지 않은 경우 `getPropertyValue`는 빈 문자열을 반환합니다. 이때는 기본값을 사용하거나 부모 요소의 스타일을 검사해야 합니다. + +## 전체 동작 예제 + +모든 단계를 합치면 다음과 같은 완전한 실행 프로그램이 됩니다: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**예상 출력 (예시):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +`
`에 배경색이 설정되지 않았다면 출력은 빈 줄이 됩니다 – 이는 상속된 스타일을 확인해야 함을 의미합니다. + +## 팁, 트릭 및 주의사항 + +| 상황 | 조치 방법 | +|-----------|------------| +| **여러 개의 `
` 요소** | `querySelectorAll("div")`을 사용하고 `NodeList`를 순회합니다. | +| **외부 CSS 파일** | HTML 파일이 올바른 경로로 CSS를 참조하도록 하고, Aspose.HTML이 자동으로 가져오게 합니다. | +| **인라인 `style` 속성만** | `getComputedStyle`은 여전히 동작합니다 – 인라인 스타일을 기본값과 병합합니다. | +| **성능 우려** | 문서를 한 번만 로드하고, 여러 요소를 조회해야 할 경우 `HTMLDocument` 객체를 재사용합니다. | +| **Android에서 실행** | Aspose.HTML for Java는 Android를 지원하지만 Android‑전용 AAR을 포함해야 합니다. | + +## 관련 주제 + +* **Jsoup vs. Aspose.HTML으로 HTML 파싱** – 언제 어느 것을 선택할지. +* **계산된 스타일을 JSON으로 내보내기** – API‑기반 프론트엔드에 유용. +* **스크린샷 자동 생성** – 계산된 스타일과 Aspose.PDF를 결합해 시각적 회귀 테스트 수행. + +--- + +### 결론 + +이제 **HTML 문서를 로드**하고, **쿼리 셀렉터 예제**를 실행한 뒤, **background-color 속성**을 추출하는 방법을 알게 되었습니다. 코드는 독립적이며 최신 JDK에서 실행 가능하고, 요소가 없거나 스타일이 정의되지 않은 경우도 우아하게 처리합니다. 여기서부터는 폰트 크기, 마진 등 다른 CSS 속성을 가져오거나, JavaScript 실행 후의 계산된 값을 얻는 등으로 확장할 수 있습니다(Aspose.HTML은 스크립트 평가도 지원합니다). + +한 번 실행해 보고, 선택자를 바꾸어 보면서 어떤 CSS 보물을 발견할 수 있는지 확인해 보세요. Happy coding! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/polish/java/conversion-html-to-various-image-formats/_index.md b/html/polish/java/conversion-html-to-various-image-formats/_index.md index 96d0ebf5f..3e28c5556 100644 --- a/html/polish/java/conversion-html-to-various-image-formats/_index.md +++ b/html/polish/java/conversion-html-to-various-image-formats/_index.md @@ -94,6 +94,8 @@ Dowiedz się, jak konwertować HTML do JPEG przy użyciu Aspose.HTML for Java. P ### [Converting HTML to PNG](./convert-html-to-png/) Dowiedz się, jak konwertować HTML do obrazów PNG w Javie przy użyciu Aspose.HTML. Kompleksowy przewodnik z instrukcjami krok po kroku. +### [Jak ustawić DPI – renderowanie HTML do PNG przy użyciu AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) + ### [Converting HTML to TIFF](./convert-html-to-tiff/) Dowiedz się, jak łatwo konwertować HTML do TIFF przy użyciu Aspose.HTML for Java. Przewodnik krok po kroku dla efektywnego zarządzania dokumentami. diff --git a/html/polish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/polish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..d84a0914c --- /dev/null +++ b/html/polish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: jak ustawić DPI przy konwertowaniu adresu URL na PNG. Dowiedz się, jak + renderować HTML do PNG, ustawiać rozmiar widoku i zapisywać HTML jako PNG przy użyciu + Aspose.HTML w Javie. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: pl +og_description: jak ustawić DPI przy konwertowaniu adresu URL na PNG. Przewodnik krok + po kroku, jak renderować HTML do PNG, kontrolować rozmiar widoku i zapisywać HTML + jako PNG przy użyciu Aspose.HTML. +og_title: jak ustawić DPI – renderowanie HTML do PNG przy użyciu AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: jak ustawić dpi – renderowanie HTML do PNG przy użyciu AsposeHTML +url: /pl/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# jak ustawić dpi – renderowanie HTML do PNG przy użyciu AsposeHTML + +Zastanawiałeś się kiedyś **jak ustawić dpi** dla obrazu w stylu zrzutu ekranu generowanego ze strony internetowej? Może potrzebujesz PNG o 300 DPI do druku lub niskiej rozdzielczości miniaturki do aplikacji mobilnej. W obu przypadkach sztuczka polega na poinformowaniu silnika renderującego, jaką logiczną wartość DPI chcesz, a następnie pozwolić mu wykonać ciężką pracę. + +W tym samouczku pobierzemy żywy URL, wyrenderujemy go do pliku PNG, **ustawimy rozmiar viewportu**, dostosujemy DPI i w końcu **zapiszemy HTML jako PNG** — wszystko przy użyciu Aspose.HTML dla Javy. Bez zewnętrznych przeglądarek, bez nieporęcznych narzędzi wiersza poleceń — po prostu czysty kod Java, który możesz wkleić do dowolnego projektu Maven lub Gradle. + +> **Pro tip:** Jeśli potrzebujesz tylko szybkiej miniaturki, możesz pozostawić DPI na 96 DPI (domyślne dla większości ekranów). Dla zasobów gotowych do druku podnieś je do 300 DPI lub wyżej. + +![how dpi example](https://example.com/images/how-to-set-dpi.png "how to set dpi example") + +## Czego będziesz potrzebować + +- **Java 17** (lub dowolny nowszy JDK). +- **Aspose.HTML for Java** 24.10 lub nowszy. Możesz pobrać go z Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Połączenie internetowe, aby pobrać docelową stronę (przykład używa `https://example.com/sample.html`). +- Uprawnienia do zapisu w folderze wyjściowym. + +To wszystko — bez Selenium, bez headless Chrome. Aspose.HTML wykonuje renderowanie w‑procesie, co oznacza, że pozostajesz w JVM i unikasz kosztów uruchamiania przeglądarki. + +## Krok 1 – Załaduj dokument HTML z URL + +Najpierw tworzymy instancję `HTMLDocument`, wskazującą na stronę, którą chcemy przechwycić. Konstruktor automatycznie pobiera HTML, parsuje go i przygotowuje DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Dlaczego to ważne:* Ładując dokument bezpośrednio, pomijasz potrzebę osobnego klienta HTTP. Aspose.HTML respektuje przekierowania, ciasteczka i nawet podstawowe uwierzytelnianie, jeśli osadzisz poświadczenia w URL. + +## Krok 2 – Zbuduj sandbox z żądanym DPI i viewportem + +**Sandbox** to sposób Aspose.HTML na naśladowanie środowiska przeglądarki. Tutaj instruujemy go, aby udawał ekran 1280 × 720 i, co najważniejsze, ustawiamy **device DPI**. Zmiana DPI zmienia gęstość pikseli renderowanego obrazu bez zmiany rozmiaru logicznego. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Dlaczego możesz chcieć dostosować te wartości:* +- **Viewport size** kontroluje zachowanie zapytań mediów CSS (`@media (max-width: …)`). +- **Device DPI** wpływa na fizyczny rozmiar obrazu przy drukowaniu. Obraz 96 DPI wygląda dobrze na ekranach; obraz 300 DPI zachowuje ostrość na papierze. + +Jeśli potrzebujesz kwadratowej miniaturki, po prostu zmień `setViewportSize(500, 500)` i utrzymaj niskie DPI. + +## Krok  – Wybierz PNG jako format wyjściowy + +Aspose.HTML obsługuje kilka formatów rastrowych (PNG, JPEG, BMP, GIF). PNG jest bezstratny, co czyni go idealnym do zrzutów ekranu, gdzie chcesz zachować każdy piksel. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Możesz także dostosować poziom kompresji (`pngOptions.setCompressionLevel(9)`), jeśli martwisz się rozmiarem pliku. + +## Krok 4 – Renderuj i zapisz obraz + +Teraz instruujemy dokument, aby **zapisał** się jako obraz. Metoda `save` przyjmuje ścieżkę pliku oraz wcześniej skonfigurowane opcje. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Po zakończeniu programu znajdziesz plik PNG w `YOUR_DIRECTORY/sandboxed.png`. Otwórz go — jeśli ustawiłeś DPI na 300, metadane obrazu to odzwierciedlą, mimo że wymiary w pikselach pozostaną 1280 × 720. + +## Krok 5 – Zweryfikuj DPI (Opcjonalnie, ale przydatne) + +Jeśli chcesz podwójnie sprawdzić, że DPI zostało naprawdę zastosowane, możesz odczytać metadane PNG przy użyciu lekkiej biblioteki takiej jak **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Powinieneś zobaczyć `300` (lub wartość, którą ustawiłeś) wydrukowaną w konsoli. Ten krok nie jest wymagany do renderowania, ale jest szybkim sprawdzeniem poprawności, szczególnie gdy generujesz zasoby do przepływu pracy drukowania. + +## Częste pytania i przypadki brzegowe + +### „Co jeśli strona używa JavaScript do ładowania treści?” + +Aspose.HTML wykonuje **ograniczony podzbiór** JavaScript. Dla większości statycznych stron działa od razu. Jeśli strona mocno polega na frameworkach po stronie klienta (React, Angular, Vue), może być konieczne wstępne renderowanie strony lub użycie przeglądarki headless. Jednak ustawianie DPI działa tak samo, gdy DOM jest gotowy. + +### „Czy mogę renderować PDF zamiast PNG?” + +Oczywiście. Zamień `ImageSaveOptions` na `PdfSaveOptions` i zmień rozszerzenie wyjściowe na `.pdf`. Ustawienie DPI nadal wpływa na rastrowy wygląd wszelkich osadzonych obrazów. + +### „A co z wysokiej rozdzielczości zrzutami ekranu dla wyświetlaczy Retina?” + +Po prostu podwój wymiary viewportu, zachowując DPI na 96 DPI, lub zachowaj viewport i podnieś DPI do 192. Wynikowy PNG będzie zawierał dwa razy więcej pikseli, dając efekt ostrego wyświetlacza Retina. + +### „Czy muszę sprzątać zasoby?” + +`HTMLDocument` implementuje `AutoCloseable`. W aplikacji produkcyjnej, otocz go blokiem try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## Pełny działający przykład (gotowy do kopiowania i wklejenia) + +Poniżej znajduje się kompletny, gotowy do uruchomienia program. Zamień `YOUR_DIRECTORY` na rzeczywisty folder na swoim komputerze. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Uruchom klasę, a otrzymasz PNG, który respektuje ustawienie **how to set dpi**, które określiłeś. + +## Zakończenie + +Przeszliśmy przez **jak ustawić dpi** przy **renderowaniu HTML do PNG**, omówiliśmy krok **set viewport size** i pokazaliśmy, jak **zapisac HTML jako PNG** przy użyciu Aspose.HTML dla Javy. Najważniejsze wnioski to: + +- Użyj **sandbox** do kontrolowania DPI i viewportu. +- Wybierz odpowiednie **ImageSaveOptions** dla wyjścia bezstratnego. +- Zweryfikuj metadane DPI, jeśli musisz zagwarantować jakość druku. + +Od tego miejsca możesz eksperymentować z różnymi wartościami DPI, większymi viewportami lub nawet przetwarzać wsadowo listę URLi. Chcesz przekonwertować całą witrynę na miniaturki PNG? Po prostu iteruj po tablicy URLi i ponownie użyj tej samej konfiguracji sandbox. + +Szczęśliwego renderowania i niech Twoje zrzuty ekranu zawsze będą perfekcyjnie pikselowe! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/polish/java/css-html-form-editing/_index.md b/html/polish/java/css-html-form-editing/_index.md index 3497842fd..851c8bf27 100644 --- a/html/polish/java/css-html-form-editing/_index.md +++ b/html/polish/java/css-html-form-editing/_index.md @@ -30,9 +30,11 @@ Teraz zmieńmy biegi i zbadajmy, jak skutecznie edytować i przesyłać formular Dowiedz się, jak używać Aspose.HTML dla Java, aby stosować zaawansowane techniki CSS, w tym niestandardowe marginesy stron i dynamiczną zawartość. Szczegółowy, praktyczny samouczek dla programistów. ### [Edycja i przesyłanie formularzy HTML za pomocą Aspose.HTML dla Java](./html-form-editing/) Dowiedz się, jak edytować i przesyłać formularze HTML programowo, korzystając z Aspose.HTML for Java, dzięki temu kompleksowemu przewodnikowi krok po kroku. +### [Jak uzyskać styl w Javie – wczytaj HTML i użyj selektora zapytań](./how-to-get-style-in-java-load-html-query-selector/) +Dowiedz się, jak w Javie pobrać style z dokumentu HTML, używając selektora zapytań w Aspose.HTML. {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/polish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/polish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..c3625b89d --- /dev/null +++ b/html/polish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: pl +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /pl/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# jak uzyskać styl w Javie – załaduj HTML i użyj query selector + +Zastanawiałeś się kiedyś, **jak uzyskać styl** elementu podczas parsowania HTML w Javie? Być może tworzysz scraper, narzędzie testowe lub po prostu musisz zweryfikować wskazówki wizualne na wygenerowanej stronie. Dobrą wiadomością jest to, że Aspose.HTML czyni to dziecinnie prostym. W tym tutorialu przejdziemy przez ładowanie dokumentu HTML, użycie **przykładu query selector** oraz odczyt **właściwości background-color** elementu `
`. Bez magii, tylko przejrzysty kod Java, który możesz skopiować‑wkleić i uruchomić. + +## Co będzie potrzebne + +Zanim zaczniemy, upewnij się, że masz: + +* **Java 17** (lub dowolny nowszy JDK) – API działa z Java 8+, ale nowsze wersje zapewniają lepszą wydajność. +* Bibliotekę **Aspose.HTML for Java** – możesz ją pobrać z Maven Central (`com.aspose:aspose-html:23.10` w momencie pisania). +* Mały plik HTML (`input.html`) zawierający przynajmniej jeden `
` z ustawionym kolorem tła w CSS, zarówno inline, jak i w arkuszu stylów. + +To wszystko. Bez dodatkowych frameworków, bez ciężkich przeglądarek – tylko czysta Java i Aspose.HTML. + +## Krok 1: Załaduj dokument HTML + +Pierwszą rzeczą, którą musisz zrobić, jest **załadowanie dokumentu HTML** do pamięci. Klasa `HTMLDocument` z Aspose.HTML abstrahuje obsługę systemu plików i udostępnia DOM, który możesz przeszukiwać. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Dlaczego to ważne:** Ładowanie dokumentu tworzy sparsowane drzewo DOM, będące podstawą wszelkich kolejnych ocen CSS lub JavaScript. Jeśli plik nie zostanie znaleziony, Aspose zgłosi opisowy `FileNotFoundException`, więc sprawdź ścieżkę podwójnie. + +### Pro tip +Jeśli pobierasz HTML z URL zamiast z pliku, po prostu przekaż ciąg URL do konstruktora – Aspose zajmie się żądaniem HTTP za Ciebie. + +## Krok 2: Użyj przykładu Query Selector + +Teraz, gdy dokument jest w pamięci, użyjmy **przykładu query selector**, aby pobrać pierwszy element `
`. Metoda `querySelector` odzwierciedla składnię selektorów CSS, którą znasz z przeglądarki. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Dlaczego to ważne:** `querySelector` zwraca pierwszy pasujący węzeł, co jest idealne, gdy potrzebujesz stylu tylko jednego elementu. Jeśli potrzebujesz wielu elementów, `querySelectorAll` zwraca `NodeList`. + +### Edge case +Jeśli selektor nie dopasuje niczego, `divElement` będzie `null`. Zawsze sprawdzaj to przed odczytem stylów: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Krok 3: Uzyskaj obliczony styl + +Mając element, kolejnym krokiem jest **parsowanie HTML w Javie** wystarczające do obliczenia ostatecznych wartości CSS. Aspose.HTML wykonuje ciężką pracę: rozwiązuje kaskadę, dziedziczenie i nawet zewnętrzne arkusze stylów. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Dlaczego to ważne:** Obliczony styl odzwierciedla dokładne wartości, które przeglądarka zastosowałaby po przetworzeniu wszystkich reguł CSS. Jest to bardziej wiarygodne niż odczytywanie surowego atrybutu `style`, który może być niekompletny. + +## Krok 4: Pobierz właściwość background‑color + +Na koniec wyciągamy **właściwość background-color**, której potrzebujemy. Metoda `getPropertyValue` zwraca wartość jako ciąg znaków (np. `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Co zobaczysz:** Jeśli Twój `
` miał `background-color: #ff5733;` zarówno inline, jak i w arkuszu stylów, konsola wyświetli coś w stylu `Computed background‑color: rgb(255, 87, 51)`. + +### Common pitfall +Gdy właściwość nie jest zdefiniowana, `getPropertyValue` zwraca pusty ciąg. To sygnał, aby albo użyć wartości domyślnej, albo sprawdzić style elementu nadrzędnego. + +## Pełny działający przykład + +Łącząc wszystko razem, oto kompletny, gotowy do uruchomienia program: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Oczekiwany wynik (przykład):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Jeśli `
` nie ma ustawionego koloru tła, wynik będzie pustą linią – to sygnał, aby przyjrzeć się stylom dziedziczonym. + +## Wskazówki, triki i rzeczy, na które warto zwrócić uwagę + +| Sytuacja | Co zrobić | +|-----------|------------| +| **Wiele elementów `
`** | Użyj `querySelectorAll("div")` i iteruj po `NodeList`. | +| **Zewnętrzne pliki CSS** | Upewnij się, że plik HTML odwołuje się do nich poprawnymi ścieżkami; Aspose.HTML pobierze je automatycznie. | +| **Tylko atrybut `style` inline** | `getComputedStyle` nadal działa – łączy style inline z wartościami domyślnymi. | +| **Obawy o wydajność** | Załaduj dokument raz, ponownie używaj obiektu `HTMLDocument`, jeśli musisz przeszukać wiele elementów. | +| **Uruchamianie na Androidzie** | Aspose.HTML for Java obsługuje Android, ale musisz dołączyć specyficzny dla Androida AAR. | + +## Powiązane tematy, które możesz zbadać + +* **Parsowanie HTML przy użyciu Jsoup vs. Aspose.HTML** – kiedy wybrać jedno, a kiedy drugie. +* **Eksportowanie obliczonych stylów do JSON** – przydatne dla front‑endów opartych na API. +* **Automatyzacja generowania zrzutów ekranu** – połącz obliczone style z Aspose.PDF w testach regresji wizualnej. + +--- + +### Podsumowanie + +Teraz wiesz, **jak uzyskać styl** dowolnego elementu, **ładować dokument HTML** przy pomocy Aspose.HTML, wykonać **przykład query selector** i wyodrębnić **właściwość background-color**. Kod jest samodzielny, działa na każdym nowoczesnym JDK i elegancko obsługuje brakujące elementy lub niezdefiniowane style. Od tego punktu możesz rozszerzyć podejście, aby pobierać rozmiary czcionek, marginesy czy nawet obliczone wartości po wykonaniu JavaScript (Aspose.HTML obsługuje także ewaluację skryptów). + +Spróbuj, zmodyfikuj selektor i zobacz, jakie inne skarby CSS możesz odkryć. Szczęśliwego kodowania! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/portuguese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/portuguese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..aa27218df --- /dev/null +++ b/html/portuguese/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Crie PDF a partir de Markdown em Java usando Aspose.HTML – um tutorial + rápido passo a passo para converter markdown em PDF, salvar markdown como PDF e + aprender o básico de Java markdown para PDF. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: pt +og_description: Crie PDF a partir de Markdown em Java com Aspose.HTML. Aprenda como + converter markdown para PDF, salvar markdown como PDF e lidar com casos de borda + comuns em um tutorial conciso. +og_title: Criar PDF a partir de Markdown em Java – One‑Liner rápido +tags: +- Java +- PDF +- Markdown +title: Criar PDF a partir de Markdown em Java – Guia Simples de Uma Linha +url: /pt/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Criar PDF a partir de Markdown em Java – Guia Simples de Uma‑Linha + +Já se perguntou como **criar PDF a partir de Markdown** sem lutar com dezenas de bibliotecas? Você não está sozinho. Muitos desenvolvedores precisam transformar suas notas `.md` em PDFs polidos para relatórios, documentação ou e‑books, e querem uma solução que funcione em uma única linha de código Java. + +Neste tutorial vamos percorrer exatamente isso: usar a biblioteca Aspose.HTML for Java para **converter markdown para pdf** e **salvar markdown como pdf** de forma limpa e mantível. Também abordaremos o tema mais amplo de **java markdown to pdf** para que você entenda o porquê de cada passo, não apenas o como. + +> **O que você vai levar** +> Um programa Java completo e executável que lê `input.md`, grava `output.pdf` e imprime uma mensagem amigável de sucesso. Além disso, você saberá como ajustar a conversão, lidar com arquivos ausentes e integrar o código em projetos maiores. + +## Pré‑requisitos – O Que Você Precisa Antes de Começar + +- **Java Development Kit (JDK) 11 ou mais recente** – o código usa `java.nio.file.Paths`, disponível desde o JDK 7, mas o JDK 11 é o LTS atual e garante compatibilidade com Aspose.HTML. +- **Aspose.HTML for Java** (versão 23.9 ou posterior). Você pode obtê‑lo no Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **Um arquivo Markdown** (`input.md`) colocado em algum lugar que você possa referenciar. Se não tiver um, crie um arquivo pequeno com alguns títulos e uma lista – a biblioteca lidará com qualquer Markdown válido. +- **Uma IDE ou o simples `javac`/`java`** – manteremos o código puro Java, sem Spring ou outros frameworks. + +> **Dica profissional:** Se você usa Maven, adicione a dependência ao seu `pom.xml` e execute `mvn clean install`. Se preferir Gradle, o equivalente é `implementation 'com.aspose:aspose-html:23.9'`. + +## Visão Geral – Criar PDF a partir de Markdown em Um Só Passo + +Abaixo está o programa completo que vamos construir. Observe a **chamada única** a `Converter.convert(...)`; esse é o coração da operação de **create pdf from markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Executar esta classe lerá `input.md`, gerará `output.pdf` e exibirá a linha de confirmação. É isso—**todo o fluxo de `create pdf from markdown` em menos de 30 linhas** (incluindo comentários). + +## Passo a Passo + +### 1️⃣ Definir os Arquivos de Origem e Destino + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Por que usamos `Paths.get`**: Ele cria um caminho independente do SO, lidando automaticamente com barras invertidas do Windows e barras normais do Unix. +- **Caso de borda**: Se o arquivo Markdown não existir, `Converter.convert` lança um `FileNotFoundException`. Você pode pré‑verificar com `Files.exists(Paths.get(markdownPath))` e exibir um erro amigável. + +### 2️⃣ Configurar Opções de Salvamento PDF (Ajustes Opcionais) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Comportamento padrão**: O PDF usará tamanho de página A4, margens padrão e incorporará fontes automaticamente. +- **Personalizando**: Quer um layout paisagem? Use `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Dica de performance**: Para arquivos Markdown grandes, você pode habilitar `pdfOptions.setEmbedStandardFonts(false)` para reduzir o tamanho do arquivo ao custo de possíveis diferenças de renderização. + +### 3️⃣ Executar a Conversão – O Coração de “Convert Markdown to PDF” + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **O que acontece nos bastidores**: Aspose.HTML analisa o Markdown para um DOM HTML interno, então renderiza esse DOM para PDF usando seu motor de layout de alta fidelidade. +- **Por que esta é a abordagem recomendada**: Comparado a pipelines caseiros de HTML‑para‑PDF (por exemplo, usando wkhtmltopdf), Aspose lida com CSS, tabelas, imagens e Unicode prontamente, tornando a questão **how to convert markdown** trivial. + +### 4️⃣ Mensagem de Confirmação + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +Um pequeno toque de UX—especialmente útil quando o programa roda como parte de um job em lote maior. + +## Lidando com Armadilhas Comuns + +| Problema | Sintoma | Solução | +|----------|---------|---------| +| **Arquivo Markdown ausente** | `FileNotFoundException` | Verifique o caminho antes: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Imagens não suportadas** | Imagens aparecem como marcadores quebrados no PDF | Garanta que as imagens sejam referenciadas com caminhos absolutos ou incorpore‑as como Base64 no Markdown. | +| **Documentos grandes causam OOM** | `OutOfMemoryError` | Aumente o heap da JVM (`-Xmx2g`) ou divida o Markdown em seções e converta cada uma separadamente, depois mescle os PDFs (Aspose oferece mesclagem com `PdfFile`). | +| **Fontes especiais ausentes** | Texto renderizado com fonte de fallback | Instale as fontes necessárias no host ou incorpore‑as manualmente via `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Estendendo a One‑Liner: Cenários do Mundo Real + +### A. Conversão em Lote de Vários Arquivos + +Se precisar **save markdown as pdf** para uma pasta inteira, envolva a conversão em um loop: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Adicionando Cabeçalho/Rodapé Personalizado + +Suponha que você queira que cada página mostre um logotipo e número de página. Use `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Agora cada PDF gerado carrega a identidade visual que você precisa—perfeito para documentação corporativa. + +### C. Integração em um Serviço Spring Boot + +Exponha a conversão como um endpoint REST: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +Agora a capacidade **java markdown to pdf** está disponível para qualquer cliente—mobile, web ou desktop. + +## Saída Esperada + +Após executar o `MdToPdfOneLiner` original, você deverá ver um novo arquivo `output.pdf` na pasta que especificou. Ao abri‑lo, verá seu conteúdo Markdown renderizado com títulos corretos, listas, blocos de código e quaisquer imagens incluídas. O PDF é totalmente pesquisável e o texto pode ser copiado—diferente de PDFs apenas de imagem. + +## Perguntas Frequentes + +**P: Isso funciona no macOS/Linux assim como no Windows?** +R: Absolutamente. A chamada `Paths.get` abstrai os separadores específicos de cada SO, e Aspose.HTML é multiplataforma. + +**P: Posso converter outras linguagens de marcação (ex.: AsciiDoc) com a mesma API?** +R: O método `Converter.convert` suporta HTML, CSS e Markdown nativamente. Para AsciiDoc, você precisaria primeiro transformá‑lo em HTML (por exemplo, usando AsciidoctorJ) e então alimentar o HTML ao Aspose. + +**P: Existe uma versão gratuita do Aspose.HTML?** +R: Aspose oferece uma licença de avaliação de 30 dias com funcionalidade completa. Para uso em produção, é necessária uma licença comercial. + +## Conclusão – Você Dominou a Criação de PDF a partir de Markdown em Java + +Levamos você do problema—*como criar PDF a partir de markdown?*—até uma solução concisa e executável, e avançamos para extensões reais como processamento em lote e serviços web. Ao aproveitar o método `Converter.convert` da Aspose.HTML, você pode **convert markdown to pdf** com apenas algumas linhas de código, mantendo a flexibilidade para personalizar tamanho de página, cabeçalhos, rodapés e configurações de performance. + +Próximos passos? Experimente trocar o `PdfSaveOptions` padrão por uma folha de estilos customizada, teste a incorporação de fontes, ou conecte a conversão ao seu pipeline CI para que todo README gere automaticamente um artefato PDF. O céu é o limite agora que você tem a base **java markdown to pdf** sob controle. + +Feliz codificação, e que seus PDFs sempre renderizem exatamente como você imaginou! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/portuguese/java/conversion-html-to-various-image-formats/_index.md b/html/portuguese/java/conversion-html-to-various-image-formats/_index.md index 77b7ccab0..28d99632b 100644 --- a/html/portuguese/java/conversion-html-to-various-image-formats/_index.md +++ b/html/portuguese/java/conversion-html-to-various-image-formats/_index.md @@ -90,6 +90,8 @@ Aprenda a converter HTML para GIF em Java usando Aspose.HTML. Um guia passo a pa Aprenda a converter HTML para JPEG com Aspose.HTML for Java. Guia passo a passo para processamento de documentos sem interrupções. ### [Convertendo HTML para PNG](./convert-html-to-png/) Aprenda a converter HTML para imagens PNG em Java com Aspose.HTML. Um guia abrangente com instruções passo a passo. +### [Como definir DPI – Renderizar HTML para PNG com AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Aprenda a definir o DPI ao renderizar HTML em PNG usando Aspose.HTML, garantindo qualidade e tamanho de imagem adequados. ### [Convertendo HTML para TIFF](./convert-html-to-tiff/) Aprenda a converter HTML para TIFF usando Aspose.HTML for Java de forma fácil. Guia passo a passo para manipulação eficiente de documentos. diff --git a/html/portuguese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/portuguese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..ce1fe6470 --- /dev/null +++ b/html/portuguese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: Como definir DPI ao converter uma URL para PNG. Aprenda a renderizar + HTML para PNG, definir o tamanho da viewport e salvar HTML como PNG usando Aspose.HTML + em Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: pt +og_description: como definir dpi ao converter uma URL para PNG. Guia passo a passo + para renderizar HTML em PNG, controlar o tamanho da viewport e salvar HTML como + PNG usando Aspose.HTML. +og_title: como definir dpi – Renderizar HTML para PNG com AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: como definir dpi – Renderizar HTML para PNG com AsposeHTML +url: /pt/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# como definir dpi – Renderizar HTML para PNG com AsposeHTML + +Já se perguntou **como definir dpi** para uma imagem semelhante a uma captura de tela gerada a partir de uma página da web? Talvez você precise de um PNG de 300 DPI para impressão, ou de uma miniatura de baixa resolução para um aplicativo móvel. Em qualquer caso, o truque é informar ao motor de renderização qual DPI lógico você deseja, e então deixá‑lo fazer o trabalho pesado. + +Neste tutorial, vamos pegar uma URL ao vivo, renderizá‑la para um arquivo PNG, **definir o tamanho da viewport**, ajustar o DPI e, finalmente, **salvar HTML como PNG** — tudo com Aspose.HTML para Java. Sem navegadores externos, sem ferramentas de linha de comando complicadas — apenas código Java limpo que você pode inserir em qualquer projeto Maven ou Gradle. + +> **Dica profissional:** Se você só precisa de uma miniatura rápida, pode manter o DPI em 96 DPI (o padrão para a maioria das telas). Para ativos prontos para impressão, aumente para 300 DPI ou mais. + +![exemplo de como definir dpi](https://example.com/images/how-to-set-dpi.png "exemplo de como definir dpi") + +## O que você precisará + +- **Java 17** (ou qualquer JDK recente). +- **Aspose.HTML for Java** 24.10 ou mais recente. Você pode obtê‑lo no Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Uma conexão à internet para buscar a página de destino (o exemplo usa `https://example.com/sample.html`). +- Permissão de escrita na pasta de saída. + +É isso — sem Selenium, sem Chrome headless. Aspose.HTML faz a renderização no processo, o que significa que você permanece dentro da JVM e evita a sobrecarga de iniciar um navegador. + +## Etapa 1 – Carregar o Documento HTML a partir de uma URL + +Primeiro criamos uma instância de `HTMLDocument` apontando para a página que queremos capturar. O construtor baixa automaticamente o HTML, analisa‑o e prepara o DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Por que isso importa:* Ao carregar o documento diretamente, você evita a necessidade de um cliente HTTP separado. Aspose.HTML respeita redirecionamentos, cookies e até autenticação básica se você incorporar credenciais na URL. + +## Etapa 2 – Construir um Sandbox com DPI e Viewport desejados + +Um **sandbox** é a forma que o Aspose.HTML tem de imitar um ambiente de navegador. Aqui instruímos que ele finja ser uma tela de 1280 × 720 e, crucialmente, definimos o **DPI do dispositivo**. Alterar o DPI muda a densidade de pixels da imagem renderizada sem alterar o tamanho lógico. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Por que você pode ajustar esses valores:* +- **Tamanho da viewport** controla como as consultas de mídia CSS (`@media (max-width: …)`) se comportam. +- **DPI do dispositivo** influencia o tamanho físico da imagem quando impressa. Uma imagem de 96 DPI parece boa em telas; uma imagem de 300 DPI mantém a nitidez no papel. + +Se você precisar de uma miniatura quadrada, basta mudar `setViewportSize(500, 500)` e manter o DPI baixo. + +## Etapa 3 – Escolher PNG como Formato de Saída + +Aspose.HTML suporta vários formatos raster (PNG, JPEG, BMP, GIF). PNG é sem perdas, o que o torna perfeito para capturas de tela onde você deseja que cada pixel seja preservado. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Você também pode ajustar o nível de compressão (`pngOptions.setCompressionLevel(9)`) se estiver preocupado com o tamanho do arquivo. + +## Etapa 4 – Renderizar e Salvar a Imagem + +Agora instruímos o documento a **salvar** a si mesmo como uma imagem. O método `save` recebe um caminho de arquivo e as opções configuradas anteriormente. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Quando o programa terminar, você encontrará um arquivo PNG em `YOUR_DIRECTORY/sandboxed.png`. Abra‑o — se você definiu o DPI para 300, os metadados da imagem refletirão isso, embora as dimensões em pixels permaneçam 1280 × 720. + +## Etapa 5 – Verificar o DPI (Opcional, mas Útil) + +Se você quiser confirmar que o DPI foi realmente aplicado, pode ler os metadados PNG com uma biblioteca leve como **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Você deverá ver `300` (ou o valor que definiu) impresso no console. Esta etapa não é necessária para a renderização, mas é uma verificação rápida, especialmente quando você está gerando ativos para um fluxo de trabalho de impressão. + +## Perguntas Frequentes & Casos Especiais + +### “E se a página usar JavaScript para carregar conteúdo?” + +Aspose.HTML executa um **subconjunto limitado** de JavaScript. Para a maioria dos sites estáticos, funciona imediatamente. Se a página depender fortemente de frameworks do lado do cliente (React, Angular, Vue), pode ser necessário pré‑renderizar a página ou usar um navegador headless. No entanto, a definição de DPI funciona da mesma forma assim que o DOM estiver pronto. + +### “Posso renderizar um PDF em vez de PNG?” + +Com certeza. Troque `ImageSaveOptions` por `PdfSaveOptions` e altere a extensão de saída para `.pdf`. A configuração de DPI ainda influencia a aparência rasterizada de quaisquer imagens incorporadas. + +### “E quanto a capturas de tela de alta resolução para telas retina?” + +Basta dobrar as dimensões da viewport mantendo o DPI em 96 DPI, ou manter a viewport e aumentar o DPI para 192. O PNG resultante conterá o dobro de pixels, proporcionando aquela nitidez típica de retina. + +### “Preciso liberar recursos?” + +`HTMLDocument` implementa `AutoCloseable`. Em um aplicativo de produção, envolva‑o em um bloco try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +## Exemplo Completo Funcional (Pronto para Copiar‑Colar) + +Abaixo está o programa completo, pronto para ser executado. Substitua `YOUR_DIRECTORY` por uma pasta real em sua máquina. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Execute a classe, e você obterá um PNG que respeita a configuração **como definir dpi** que você especificou. + +## Conclusão + +Nós percorremos **como definir dpi** ao **renderizar HTML para PNG**, cobrimos a etapa **definir tamanho da viewport** e mostramos como **salvar HTML como PNG** usando Aspose.HTML para Java. Os principais pontos são: + +- Use um **sandbox** para controlar DPI e viewport. +- Escolha o **ImageSaveOptions** correto para saída sem perdas. +- Verifique os metadados de DPI se precisar garantir a qualidade de impressão. + +A partir daqui você pode experimentar diferentes valores de DPI, viewports maiores ou até processar em lote uma lista de URLs. Quer converter um site inteiro em miniaturas PNG? Basta percorrer um array de URLs e reutilizar a mesma configuração de sandbox. + +Boa renderização, e que suas capturas de tela sejam sempre perfeitas em pixels! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/russian/java/conversion-html-to-other-formats/_index.md b/html/russian/java/conversion-html-to-other-formats/_index.md index 4c0f72ade..272845abd 100644 --- a/html/russian/java/conversion-html-to-other-formats/_index.md +++ b/html/russian/java/conversion-html-to-other-formats/_index.md @@ -105,6 +105,9 @@ Aspose.HTML for Java упрощает процесс конвертации HTML ### [Конвертация SVG в XPS](./convert-svg-to-xps/) Узнайте, как конвертировать SVG в XPS с помощью Aspose.HTML for Java. Простое пошаговое руководство для бесшовных конвертаций. +### [Создание PDF из Markdown в Java – простой однострочный гид](./create-pdf-from-markdown-in-java-simple-one-liner-guide/) +Узнайте, как в одну строку преобразовать Markdown в PDF в Java с помощью Aspose.HTML. + ## Часто задаваемые вопросы **Q: Можно ли использовать Aspose.HTML for Java в коммерческом приложении?** @@ -133,4 +136,4 @@ A: Да. Вы можете задать заголовок, автора, тем {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/russian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/russian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..cedd1388d --- /dev/null +++ b/html/russian/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Создайте PDF из Markdown в Java с помощью Aspose.HTML — быстрый пошаговый + учебник по конвертации markdown в PDF, сохранению markdown в PDF и изучению основ + Java markdown в PDF. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: ru +og_description: Создайте PDF из Markdown в Java с помощью Aspose.HTML. Узнайте, как + конвертировать markdown в PDF, сохранять markdown как PDF и решать распространённые + крайние случаи в кратком руководстве. +og_title: Создать PDF из Markdown в Java – Быстрый однострочник +tags: +- Java +- PDF +- Markdown +title: Создание PDF из Markdown в Java — простой однострочный гид +url: /ru/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Создание PDF из Markdown в Java – простой однострочный гид + +Когда‑нибудь задумывались, как **создать PDF из Markdown** без борьбы с десятками библиотек? Вы не одиноки. Многие разработчики нужно превратить свои заметки `.md` в отшлифованные PDF для отчётов, документации или электронных книг, и им требуется решение, которое работает одной строкой кода Java. + +В этом руководстве мы пройдём именно этот путь: используя библиотеку Aspose.HTML for Java для **конвертации markdown в pdf** и **сохранения markdown как pdf** чистым, поддерживаемым способом. Мы также коснёмся более широкой темы **java markdown to pdf**, чтобы вы понимали, почему делаем каждый шаг, а не только как. + +> **Что вы получите** +> Полную, исполняемую программу на Java, которая читает `input.md`, пишет `output.pdf` и выводит дружелюбное сообщение об успехе. Кроме того, вы узнаете, как настроить конвертацию, обработать отсутствие файлов и интегрировать код в более крупные проекты. + +## Предварительные требования – Что нужно перед началом + +- **Java Development Kit (JDK) 11 или новее** – код использует `java.nio.file.Paths`, доступный с JDK 7, но JDK 11 – текущий LTS и гарантирует совместимость с Aspose.HTML. +- **Aspose.HTML for Java** (версия 23.9 или новее). Вы можете получить её из Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **Файл Markdown** (`input.md`), размещённый в доступном месте. Если у вас его нет, создайте небольшой файл с парой заголовков и списком – библиотека обработает любой корректный Markdown. +- **IDE или обычный `javac`/`java`** – мы будем использовать чистый Java, без Spring и других фреймворков. + +> **Pro tip:** Если вы используете Maven, добавьте зависимость в ваш `pom.xml` и выполните `mvn clean install`. Если предпочитаете Gradle, эквивалент будет `implementation 'com.aspose:aspose-html:23.9'`. + +## Обзор – Создание PDF из Markdown в один шаг + +Ниже представлен полный код программы, которую мы построим. Обратите внимание на **единственный вызов** `Converter.convert(...)`; это сердце операции **create pdf from markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Запуск этого класса прочитает `input.md`, сгенерирует `output.pdf` и выведет строку подтверждения. И всё—**полный workflow `create pdf from markdown` в менее чем 30 строках** (включая комментарии). + +## Пошаговый разбор + +### 1️⃣ Определение исходного и целевого файлов + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Почему мы используем `Paths.get`**: он формирует путь, независимый от ОС, автоматически обрабатывая обратные слеши Windows и прямые слеши Unix. +- **Крайний случай**: если файл Markdown не существует, `Converter.convert` бросит `FileNotFoundException`. Вы можете предварительно проверить наличие с помощью `Files.exists(Paths.get(markdownPath))` и вывести дружелюбную ошибку. + +### 2️⃣ Настройка параметров сохранения PDF (необязательные правки) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Поведение по умолчанию**: PDF будет использовать размер страницы A4, стандартные отступы и автоматически встраивать шрифты. +- **Настройка**: хотите альбомную ориентацию? Используйте `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Подсказка по производительности**: для больших файлов Markdown можно отключить встраивание стандартных шрифтов через `pdfOptions.setEmbedStandardFonts(false)`, что уменьшит размер файла ценой возможных различий в рендеринге. + +### 3️⃣ Выполнение конвертации – Сердце «Convert Markdown to PDF» + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **Что происходит под капотом**: Aspose.HTML парсит Markdown в внутренний HTML‑DOM, а затем рендерит этот DOM в PDF с помощью своего высокоточного движка раскладки. +- **Почему это рекомендуемый подход**: по сравнению с самописными конвейерами HTML‑to‑PDF (например, wkhtmltopdf), Aspose обрабатывает CSS, таблицы, изображения и Unicode «из коробки», делая вопрос **how to convert markdown** тривиальным. + +### 4️⃣ Сообщение подтверждения + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +Небольшой UX‑шаг — особенно полезен, когда программа запускается как часть более крупного пакетного задания. + +## Обработка распространённых проблем + +| Проблема | Симптом | Решение | +|----------|----------|----------| +| **Отсутствует файл Markdown** | `FileNotFoundException` | Проверьте путь заранее: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Неподдерживаемые изображения** | Изображения отображаются как сломанные заполнители в PDF | Убедитесь, что изображения указаны абсолютными путями или внедрены как Base64 в Markdown. | +| **Большие документы вызывают OOM** | `OutOfMemoryError` | Увеличьте размер кучи JVM (`-Xmx2g`) или разбейте Markdown на секции и конвертируйте их по отдельности, затем объедините PDF (Aspose предлагает слияние через `PdfFile`). | +| **Отсутствуют специальные шрифты** | Текст отображается шрифтом‑заменой | Установите необходимые шрифты на хосте или вручную встраивайте их через `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Расширение однострочника: реальные сценарии + +### A. Пакетная конвертация нескольких файлов + +Если нужно **save markdown as pdf** для всей папки, оберните конвертацию в цикл: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Добавление пользовательского заголовка/подвала + +Предположим, вы хотите, чтобы на каждой странице отображался логотип и номер страницы. Используйте `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Теперь каждый сгенерированный PDF несёт нужный брендинг — идеально для корпоративной документации. + +### C. Интеграция в сервис Spring Boot + +Откройте конвертацию как REST‑endpoint: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +Теперь возможность **java markdown to pdf** доступна любому клиенту — мобильному, веб‑ или настольному. + +## Ожидаемый результат + +После запуска оригинального `MdToPdfOneLiner` вы должны увидеть новый файл `output.pdf` в указанной папке. Открыв его, вы увидите ваш Markdown, отрендеренный с правильными заголовками, списками, блоками кода и всеми включёнными изображениями. PDF полностью индексируемый, текст можно копировать — в отличие от PDF, состоящих только из изображений. + +## Часто задаваемые вопросы + +**В: Работает ли это на macOS/Linux так же, как и на Windows?** +О: Абсолютно. Вызов `Paths.get` абстрагирует разделители, специфичные для ОС, а Aspose.HTML кроссплатформен. + +**В: Могу ли я конвертировать другие языки разметки (например, AsciiDoc) тем же API?** +О: Метод `Converter.convert` поддерживает HTML, CSS и Markdown «из коробки». Для AsciiDoc сначала нужно преобразовать его в HTML (например, с помощью AsciidoctorJ), а затем передать полученный HTML в Aspose. + +**В: Есть ли бесплатная версия Aspose.HTML?** +О: Aspose предлагает 30‑дневную оценочную лицензию с полной функциональностью. Для продакшн‑использования требуется коммерческая лицензия. + +## Заключение – Вы освоили создание PDF из Markdown в Java + +Мы провели вас от постановки задачи — *как создать PDF из markdown?* — через лаконичное, исполняемое решение к реальным расширениям, таким как пакетная обработка и веб‑сервисы. Используя метод `Converter.convert` из Aspose.HTML, вы можете **convert markdown to pdf** всего несколькими строками кода, сохраняя возможность настраивать размер страницы, заголовки, подвали и параметры производительности. + +Что дальше? Попробуйте заменить стандартные `PdfSaveOptions` на собственную таблицу стилей, поэкспериментируйте с встраиванием шрифтов или подключите конвертацию к вашему CI‑pipeline, чтобы каждый README автоматически получал PDF‑артефакт. Возможности безграничны, как только у вас под рукой будет фундамент **java markdown to pdf**. + +Счастливого кодинга, и пусть ваши PDF всегда отображаются точно так, как вы себе представляете! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/russian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/russian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..576a61467 --- /dev/null +++ b/html/russian/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: как установить DPI при конвертации URL в PNG. Узнайте, как рендерить + HTML в PNG, задавать размер области просмотра и сохранять HTML как PNG с помощью + Aspose.HTML в Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: ru +og_description: как установить DPI при конвертации URL в PNG. Пошаговое руководство + по рендерингу HTML в PNG, управлению размером области просмотра и сохранению HTML + как PNG с помощью Aspose.HTML. +og_title: как установить dpi – рендеринг HTML в PNG с помощью AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: как задать dpi – преобразование HTML в PNG с AsposeHTML +url: /ru/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# как установить dpi – рендеринг HTML в PNG с AsposeHTML + +Когда‑нибудь задавались вопросом, **как установить dpi** для изображения, похожего на скриншот, сгенерированного из веб‑страницы? Возможно, вам нужен PNG с 300 DPI для печати или низкокачественная миниатюра для мобильного приложения. В любом случае, трюк заключается в том, чтобы сообщить движку рендеринга желаемый логический DPI, а затем позволить ему выполнить всю тяжелую работу. + +В этом руководстве мы возьмём живой URL, отрендерим его в файл PNG, **установим размер области просмотра**, скорректируем DPI и, наконец, **сохраним HTML как PNG** — всё это с помощью Aspose.HTML for Java. Никаких внешних браузеров, никаких громоздких инструментов командной строки — только чистый Java‑код, который можно добавить в любой проект Maven или Gradle. + +> **Совет:** Если вам нужна лишь быстрая миниатюра, можете оставить DPI на уровне 96 DPI (по умолчанию для большинства экранов). Для готовых к печати ресурсов увеличьте его до 300 DPI или выше. + +![пример установки dpi](https://example.com/images/how-to-set-dpi.png "пример установки dpi") + +## Что понадобится + +- **Java 17** (или любой современный JDK). +- **Aspose.HTML for Java** 24.10 или новее. Вы можете получить его из Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Подключение к Интернету для получения целевой страницы (в примере используется `https://example.com/sample.html`). +- Разрешение на запись в папку вывода. + +И всё — без Selenium, без headless Chrome. Aspose.HTML выполняет рендеринг в процессе, что означает, что вы остаётесь внутри JVM и избегаете накладных расходов на запуск браузера. + +## Шаг 1 – Загрузка HTML‑документа из URL + +Сначала мы создаём экземпляр `HTMLDocument`, указывающий на страницу, которую хотим захватить. Конструктор автоматически загружает HTML, парсит его и подготавливает DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Почему это важно:* Загружая документ напрямую, вы избавляетесь от необходимости использовать отдельный HTTP‑клиент. Aspose.HTML учитывает перенаправления, cookies и даже базовую аутентификацию, если вы встраиваете учётные данные в URL. + +## Шаг 2 – Создание sandbox‑окружения с нужным DPI и областью просмотра + +**Sandbox** — это способ Aspose.HTML имитировать браузерную среду. Здесь мы заставляем его «думать», что это экран 1280 × 720, и, что особенно важно, задаём **device DPI**. Изменение DPI меняет плотность пикселей отрендеренного изображения без изменения логического размера. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Почему вы можете менять эти значения:* +- **Viewport size** контролирует, как работают CSS‑медиа‑запросы (`@media (max-width: …)`). +- **Device DPI** влияет на физический размер изображения при печати. Изображение с 96 DPI выглядит нормально на экранах; изображение с 300 DPI сохраняет чёткость на бумаге. + +Если вам нужна квадратная миниатюра, просто измените `setViewportSize(500, 500)` и оставьте DPI низким. + +## Шаг 3 – Выбор PNG в качестве формата вывода + +Aspose.HTML поддерживает несколько растровых форматов (PNG, JPEG, BMP, GIF). PNG — без потерь, что делает его идеальным для скриншотов, где требуется сохранить каждый пиксель. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Вы также можете настроить уровень сжатия (`pngOptions.setCompressionLevel(9)`), если вас беспокоит размер файла. + +## Шаг 4 – Рендеринг и сохранение изображения + +Теперь мы просим документ **сохранить** себя как изображение. Метод `save` принимает путь к файлу и ранее настроенные параметры. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Когда программа завершится, вы найдёте PNG‑файл по пути `YOUR_DIRECTORY/sandboxed.png`. Откройте его — если вы задали DPI 300, метаданные изображения отразят это, хотя пиксельные размеры останутся 1280 × 720. + +## Шаг 5 – Проверка DPI (необязательно, но полезно) + +Если вы хотите двойной проверкой убедиться, что DPI действительно применён, можете прочитать метаданные PNG с помощью лёгкой библиотеки, такой как **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Вы должны увидеть `300` (или то значение, которое задали) выведенным в консоль. Этот шаг не обязателен для **рендеринга**, но это быстрая проверка, особенно когда вы **генерируете** ресурсы для **печати**. + +## Часто задаваемые вопросы и особые случаи + +### «Что если страница использует JavaScript для загрузки контента?» + +Aspose.HTML выполняет **ограниченный набор** JavaScript. Для большинства статических сайтов это работает сразу же. Если страница сильно зависит от клиентских **фреймворков** (React, Angular, Vue), вам может потребоваться предварительно отрендерить страницу или использовать headless‑браузер. Тем не менее, установка DPI работает одинаково, как только DOM готов. + +### «Можно ли отрендерить PDF вместо PNG?» + +Конечно. Замените `ImageSaveOptions` на `PdfSaveOptions` и измените расширение выходного файла на `.pdf`. Настройка DPI по‑прежнему влияет на растровый вид любых встроенных изображений. + +### «А как насчёт скриншотов высокого разрешения для Retina‑дисплеев?» + +Просто удвойте размеры viewport, оставив DPI на уровне 96 DPI, либо оставьте viewport и увеличьте DPI до 192. Получившийся PNG будет содержать вдвое больше пикселей, обеспечивая чёткое ощущение Retina. + +### «Нужно ли освобождать ресурсы?» + +`HTMLDocument` реализует `AutoCloseable`. В продакшн‑приложении оберните его в блок try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Это гарантирует своевременное освобождение нативных ресурсов. + +## Полный рабочий пример (готовый к копированию и вставке) + +Ниже представлен полный, готовый к запуску код. Замените `YOUR_DIRECTORY` реальной папкой на вашем компьютере. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Запустите класс, и вы получите PNG, который учитывает указанные вами настройки **how to set dpi**. + +## Заключение + +Мы прошли процесс **how to set dpi** при **рендеринге HTML в PNG**, рассмотрели шаг **set viewport size** и показали, как **сохранить HTML как PNG** с помощью Aspose.HTML for Java. Основные выводы: + +- Используйте **sandbox** для управления DPI и viewport. +- Выбирайте правильные **ImageSaveOptions** для безпотерьного вывода. +- Проверьте метаданные DPI, если необходимо гарантировать качество печати. + +Отсюда вы можете экспериментировать с различными значениями DPI, большими viewport или даже пакетно обрабатывать список URL‑ов. Хотите преобразовать весь сайт в PNG‑миниатюры? Просто пройдитесь по массиву URL‑ов и повторно используйте ту же конфигурацию sandbox. + +Удачного рендеринга, и пусть ваши скриншоты всегда будут пиксельно‑идеальными! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/russian/java/css-html-form-editing/_index.md b/html/russian/java/css-html-form-editing/_index.md index 27ac43d9f..29201d617 100644 --- a/html/russian/java/css-html-form-editing/_index.md +++ b/html/russian/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ url: /ru/java/css-html-form-editing/ Узнайте, как использовать Aspose.HTML для Java, чтобы применять передовые методы CSS, включая пользовательские поля страниц и динамический контент. Подробное практическое руководство для разработчиков. ### [Редактирование и отправка HTML-форм с помощью Aspose.HTML для Java](./html-form-editing/) Узнайте, как программно редактировать и отправлять HTML-формы с помощью Aspose.HTML для Java, в этом подробном пошаговом руководстве. +### [Как получить стиль в Java – загрузить HTML и использовать query selector](./how-to-get-style-in-java-load-html-query-selector/) +Узнайте, как загрузить HTML в Java и получить стили с помощью querySelector. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/russian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/russian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..125bf5626 --- /dev/null +++ b/html/russian/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,183 @@ +--- +category: general +date: 2026-01-14 +description: как получить стиль в Java – узнайте, как загрузить HTML‑документ, использовать + пример query selector и прочитать свойство background-color с помощью Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: ru +og_description: как получить стиль в Java – пошаговое руководство по загрузке HTML‑документа, + выполнению примера query selector и получению свойства background-color. +og_title: как получить стиль в Java – загрузить HTML и использовать query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: как получить стиль в Java – загрузка HTML и селектор запросов +url: /ru/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# как получить стиль в Java – загрузка HTML и query selector + +Когда‑нибудь задавались вопросом **как получить стиль** элемента при парсинге HTML на Java? Возможно, вы создаёте скрейпер, инструмент тестирования или просто хотите проверить визуальные подсказки на сгенерированной странице. Хорошая новость: Aspose.HTML делает это проще простого. В этом руководстве мы пройдем процесс загрузки HTML‑документа, использования **примера query selector**, и, наконец, чтения **свойства background-color** у элемента `
`. Никакой магии, только чистый Java‑код, который можно скопировать‑вставить и запустить. + +## Что вам понадобится + +* **Java 17** (или любой современный JDK) – API работает с Java 8+, но более новые версии дают лучшую производительность. +* **Aspose.HTML for Java** библиотека – её можно получить из Maven Central (`com.aspose:aspose-html:23.10` на момент написания). +* Маленький HTML‑файл (`input.html`), содержащий хотя бы один `
` с установленным CSS‑свойством background‑color, заданным либо инлайн, либо через таблицу стилей. + +Это всё. Никаких дополнительных фреймворков, тяжёлых браузеров – только чистый Java и Aspose.HTML. + +## Шаг 1: Загрузка HTML‑документа + +Первое, что нужно сделать, – **load html document** в память. Класс `HTMLDocument` из Aspose.HTML абстрагирует работу с файловой системой и предоставляет DOM, который можно запросить. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Почему это важно:** Загрузка документа создаёт разобранное дерево DOM, которое является основой для любой последующей оценки CSS или JavaScript. Если файл не найден, Aspose бросает информативный `FileNotFoundException`, поэтому проверьте путь дважды. + +### Совет +Если вы получаете HTML по URL вместо файла, просто передайте строку URL в конструктор – Aspose выполнит HTTP‑запрос за вас. + +## Шаг 2: Использование примера query selector + +Теперь, когда документ находится в памяти, давайте **query selector example** для получения первого элемента `
`. Метод `querySelector` использует синтаксис CSS‑селекторов, знакомый вам из браузера. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Почему это важно:** `querySelector` возвращает первый подходящий узел, что идеально, когда нужен стиль только одного элемента. Если требуется несколько элементов, `querySelectorAll` возвращает `NodeList`. + +### Пограничный случай +Если селектор ничего не найдёт, `divElement` будет `null`. Всегда проверяйте это перед тем, как читать стили: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Шаг 3: Получение вычисленного стиля + +Имея элемент, следующий шаг – **parse html java** достаточно, чтобы вычислить окончательные значения CSS. Aspose.HTML делает тяжёлую работу: он разрешает каскад, наследование и даже внешние таблицы стилей. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Почему это важно:** Вычисленный стиль отражает точные значения, которые браузер применил бы после обработки всех правил CSS. Это надёжнее, чем чтение «сырого» атрибута `style`, который может быть неполным. + +## Шаг 4: Получение свойства background‑color + +Наконец, получаем **background-color property**, который нам нужен. Метод `getPropertyValue` возвращает значение в виде строки (например, `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Что вы увидите:** Если ваш `
` имел `background-color: #ff5733;` инлайн или через таблицу стилей, консоль выведет что‑то вроде `Computed background‑color: rgb(255, 87, 51)`. + +### Распространённая ошибка +Когда свойство не определено, `getPropertyValue` возвращает пустую строку. Это сигнал к тому, чтобы либо использовать значение по умолчанию, либо проверить стили родительского элемента. + +## Полный рабочий пример + +Объединив всё вместе, получаем полностью готовую к запуску программу: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Ожидаемый вывод (пример):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Если у `
` не задан цвет фона, вывод будет пустой строкой – это ваш сигнал посмотреть на наследуемые стили. + +## Советы, хитрости и на что обратить внимание + +| Ситуация | Что делать | +|-----------|------------| +| **Multiple `
` elements** | Use `querySelectorAll("div")` and iterate over the `NodeList`. | +| **External CSS files** | Ensure the HTML file references them with correct paths; Aspose.HTML will fetch them automatically. | +| **Inline `style` attribute only** | `getComputedStyle` still works – it merges inline styles with defaults. | +| **Performance concerns** | Load the document once, reuse the `HTMLDocument` object if you need to query many elements. | +| **Running on Android** | Aspose.HTML for Java supports Android, but you’ll need to include the Android‑specific AAR. | + +## Связанные темы, которые могут быть интересны + +* **Parsing HTML with Jsoup vs. Aspose.HTML** – when to pick one over the other. +* **Exporting computed styles to JSON** – useful for API‑driven front‑ends. +* **Automating screenshot generation** – combine computed styles with Aspose.PDF for visual regression testing. + +--- + +### Заключение + +Теперь вы знаете **how to get style** любого элемента, когда **load html document** с помощью Aspose.HTML, выполняете **query selector example** и извлекаете **background-color property**. Код автономный, работает на любом современном JDK и корректно обрабатывает отсутствие элементов или неопределённые стили. Отсюда вы можете расширить подход для получения размеров шрифтов, отступов или даже вычисленных значений после выполнения JavaScript (Aspose.HTML также поддерживает оценку скриптов). + +Попробуйте, измените селектор и посмотрите, какие ещё CSS‑сокровища можно обнаружить. Приятного кодинга! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/spanish/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md b/html/spanish/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md new file mode 100644 index 000000000..e22c068d6 --- /dev/null +++ b/html/spanish/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/_index.md @@ -0,0 +1,220 @@ +--- +category: general +date: 2026-01-14 +description: Crear PDF a partir de Markdown en Java usando Aspose.HTML – un tutorial + rápido paso a paso para convertir markdown a PDF, guardar markdown como PDF y aprender + los conceptos básicos de Java markdown a PDF. +draft: false +keywords: +- create pdf from markdown +- convert markdown to pdf +- how to convert markdown +- save markdown as pdf +- java markdown to pdf +language: es +og_description: Crear PDF a partir de Markdown en Java con Aspose.HTML. Aprende cómo + convertir markdown a PDF, guardar markdown como PDF y manejar casos límite comunes + en un tutorial conciso. +og_title: Crear PDF a partir de Markdown en Java – Una línea rápida +tags: +- Java +- PDF +- Markdown +title: Crear PDF desde Markdown en Java – Guía simple de una sola línea +url: /es/java/conversion-html-to-other-formats/create-pdf-from-markdown-in-java-simple-one-liner-guide/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Crear PDF a partir de Markdown en Java – Guía Simple de Una Línea + +¿Alguna vez te has preguntado cómo **crear PDF a partir de Markdown** sin luchar con docenas de bibliotecas? No estás solo. Muchos desarrolladores necesitan convertir sus notas `.md` en PDFs pulidos para informes, documentación o libros electrónicos, y buscan una solución que funcione en una sola línea de código Java. + +En este tutorial recorreremos exactamente eso: usar la biblioteca Aspose.HTML para Java para **convertir markdown a pdf** y **guardar markdown como pdf** de manera limpia y mantenible. También abordaremos el tema más amplio de **java markdown to pdf** para que comprendas el porqué detrás de cada paso, no solo el cómo. + +> **Lo que obtendrás** +> Un programa Java completo y ejecutable que lee `input.md`, escribe `output.pdf` y muestra un mensaje de éxito amigable. Además, sabrás cómo ajustar la conversión, manejar archivos faltantes e integrar el código en proyectos más grandes. + +## Requisitos previos – Lo que necesitas antes de comenzar + +- **Java Development Kit (JDK) 11 o superior** – el código usa `java.nio.file.Paths`, disponible desde JDK 7, pero JDK 11 es la LTS actual y garantiza compatibilidad con Aspose.HTML. +- **Aspose.HTML para Java** (versión 23.9 o posterior). Puedes obtenerlo desde Maven Central: + ```xml + + com.aspose + aspose-html + 23.9 + + ``` +- **Un archivo Markdown** (`input.md`) ubicado en algún lugar al que puedas referenciar. Si no tienes uno, crea un archivo pequeño con un par de encabezados y una lista; la biblioteca manejará cualquier Markdown válido. +- **Un IDE o `javac`/`java`** – mantendremos el código puro Java, sin Spring ni otros frameworks. + +> **Consejo profesional:** Si usas Maven, agrega la dependencia a tu `pom.xml` y ejecuta `mvn clean install`. Si prefieres Gradle, el equivalente es `implementation 'com.aspose:aspose-html:23.9'`. + +## Visión general – Crear PDF a partir de Markdown en un solo paso + +A continuación tienes el programa completo que construiremos. Observa la **llamada única** a `Converter.convert(...)`; ese es el corazón de la operación **create pdf from markdown**. + +```java +import com.aspose.html.converters.Converter; +import com.aspose.html.converters.PdfSaveOptions; +import java.nio.file.Paths; + +/** + * MdToPdfOneLiner demonstrates how to create PDF from Markdown + * using Aspose.HTML for Java. + */ +public class MdToPdfOneLiner { + public static void main(String[] args) throws Exception { + + // 1️⃣ Define source Markdown and target PDF paths + String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); + String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); + + // 2️⃣ Create default PDF save options (you can customize later) + PdfSaveOptions pdfOptions = new PdfSaveOptions(); + + // 3️⃣ Convert the Markdown document to PDF – the core of create PDF from markdown + Converter.convert(markdownPath, pdfPath, pdfOptions); + + // 4️⃣ Let the user know everything went smoothly + System.out.println("Markdown has been converted to PDF."); + } +} +``` + +Ejecutar esta clase leerá `input.md`, generará `output.pdf` y mostrará la línea de confirmación. Eso es todo—**todo el flujo `create pdf from markdown` en menos de 30 líneas** (incluyendo comentarios). + +## Desglose paso a paso + +### 1️⃣ Definir los archivos de origen y destino + +```java +String markdownPath = Paths.get("YOUR_DIRECTORY/input.md").toString(); +String pdfPath = Paths.get("YOUR_DIRECTORY/output.pdf").toString(); +``` + +- **Por qué usamos `Paths.get`**: construye una ruta independiente del SO, manejando automáticamente las barras invertidas de Windows y las barras normales de Unix. +- **Caso límite**: si el archivo Markdown no existe, `Converter.convert` lanza una `FileNotFoundException`. Puedes pre‑verificar con `Files.exists(Paths.get(markdownPath))` y mostrar un error amigable. + +### 2️⃣ Configurar opciones de guardado PDF (Ajustes opcionales) + +```java +PdfSaveOptions pdfOptions = new PdfSaveOptions(); +``` + +- **Comportamiento por defecto**: el PDF usará tamaño de página A4, márgenes predeterminados y incrustará fuentes automáticamente. +- **Personalización**: ¿Quieres un diseño horizontal? Usa `pdfOptions.setPageSize(PdfPageSize.A5); pdfOptions.setOrientation(PageOrientation.Landscape);`. +- **Consejo de rendimiento**: para archivos Markdown grandes, puedes habilitar `pdfOptions.setEmbedStandardFonts(false)` para reducir el tamaño del archivo a costa de posibles diferencias de renderizado. + +### 3️⃣ Realizar la conversión – El corazón de “Convertir Markdown a PDF” + +```java +Converter.convert(markdownPath, pdfPath, pdfOptions); +``` + +- **Qué ocurre bajo el capó**: Aspose.HTML analiza el Markdown a un DOM HTML interno, luego renderiza ese DOM a PDF usando su motor de maquetación de alta fidelidad. +- **Por qué este es el enfoque recomendado**: comparado con pipelines caseros HTML‑a‑PDF (p. ej., wkhtmltopdf), Aspose maneja CSS, tablas, imágenes y Unicode de forma nativa, haciendo trivial la pregunta **how to convert markdown**. + +### 4️⃣ Mensaje de confirmación + +```java +System.out.println("Markdown has been converted to PDF."); +``` + +Un pequeño toque de UX—especialmente útil cuando el programa se ejecuta como parte de un trabajo por lotes más grande. + +## Manejo de problemas comunes + +| Problema | Síntoma | Solución | +|----------|---------|----------| +| **Archivo Markdown faltante** | `FileNotFoundException` | Verifica la ruta antes: `if (!Files.exists(Paths.get(markdownPath))) { System.err.println("File not found"); return; }` | +| **Imágenes no compatibles** | Las imágenes aparecen como marcadores rotos en el PDF | Asegúrate de que las imágenes se referencien con rutas absolutas o incrústalas como Base64 en el Markdown. | +| **Documentos grandes provocan OOM** | `OutOfMemoryError` | Aumenta el heap de JVM (`-Xmx2g`) o divide el Markdown en secciones y conviértelas por separado, luego combina los PDFs (Aspose ofrece fusión con `PdfFile`). | +| **Fuentes especiales ausentes** | Texto renderizado con fuente de reemplazo | Instala las fuentes requeridas en el host o incrústalas manualmente vía `pdfOptions.getFontEmbeddingMode().setEmbeddingMode(FontEmbeddingMode.Always);` | + +## Extender la línea única: Escenarios del mundo real + +### A. Conversión por lotes de varios archivos + +Si necesitas **save markdown as pdf** para una carpeta completa, envuelve la conversión en un bucle: + +```java +Path inputDir = Paths.get("YOUR_DIRECTORY/md"); +Path outputDir = Paths.get("YOUR_DIRECTORY/pdf"); + +Files.createDirectories(outputDir); + +try (DirectoryStream stream = Files.newDirectoryStream(inputDir, "*.md")) { + for (Path mdFile : stream) { + String pdfFile = outputDir.resolve(mdFile.getFileName().toString().replace(".md", ".pdf")).toString(); + Converter.convert(mdFile.toString(), pdfFile, new PdfSaveOptions()); + System.out.println(mdFile.getFileName() + " → " + pdfFile); + } +} +``` + +### B. Añadir encabezado/pie de página personalizado + +Supongamos que quieres que cada página muestre un logotipo y número de página. Usa `PdfSaveOptions`: + +```java +PdfSaveOptions options = new PdfSaveOptions(); +options.getHeader().setHtml("
My Report
"); +options.getFooter().setHtml("
Page {page} of {total}
"); +``` + +Ahora cada PDF generado lleva la marca que necesitas—perfecto para documentación corporativa. + +### C. Integración en un servicio Spring Boot + +Expón la conversión como un endpoint REST: + +```java +@PostMapping("/convert") +public ResponseEntity convert(@RequestParam MultipartFile file) throws Exception { + Path tempMd = Files.createTempFile("input", ".md"); + Files.write(tempMd, file.getBytes()); + + Path tempPdf = Files.createTempFile("output", ".pdf"); + Converter.convert(tempMd.toString(), tempPdf.toString(), new PdfSaveOptions()); + + byte[] pdfBytes = Files.readAllBytes(tempPdf); + return ResponseEntity.ok() + .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"output.pdf\"") + .contentType(MediaType.APPLICATION_PDF) + .body(pdfBytes); +} +``` + +Así la capacidad **java markdown to pdf** está disponible para cualquier cliente—móvil, web o escritorio. + +## Resultado esperado + +Después de ejecutar el `MdToPdfOneLiner` original, deberías ver un nuevo archivo `output.pdf` en la carpeta que especificaste. Al abrirlo, se mostrará tu contenido Markdown renderizado con encabezados, listas, bloques de código y cualquier imagen que hayas incluido. El PDF es totalmente searchable y el texto se puede copiar—a diferencia de los PDFs solo de imagen. + +## Preguntas frecuentes + +**P: ¿Esto funciona en macOS/Linux además de Windows?** +R: Absolutamente. La llamada `Paths.get` abstrae los separadores específicos del SO, y Aspose.HTML es multiplataforma. + +**P: ¿Puedo convertir otros lenguajes de marcado (p. ej., AsciiDoc) con la misma API?** +R: El método `Converter.convert` soporta HTML, CSS y Markdown de forma nativa. Para AsciiDoc primero deberías transformarlo a HTML (p. ej., usando AsciidoctorJ) y luego pasar el HTML a Aspose. + +**P: ¿Existe una versión gratuita de Aspose.HTML?** +R: Aspose ofrece una licencia de evaluación de 30 días con funcionalidad completa. Para uso en producción se requiere una licencia comercial. + +## Conclusión – Has dominado la creación de PDF a partir de Markdown en Java + +Te hemos llevado desde la pregunta inicial—*¿cómo crear PDF a partir de markdown?*—hasta una solución concisa y ejecutable, y luego a extensiones del mundo real como procesamiento por lotes y servicios web. Aprovechando el método `Converter.convert` de Aspose.HTML, puedes **convert markdown to pdf** con solo unas pocas líneas de código, manteniendo la flexibilidad para personalizar tamaño de página, encabezados, pies y ajustes de rendimiento. + +¿Próximos pasos? Prueba cambiar las `PdfSaveOptions` predeterminadas por una hoja de estilo personalizada, experimenta con la incrustación de fuentes o integra la conversión en tu pipeline CI para que cada README genere automáticamente un artefacto PDF. El cielo es el límite una vez que tengas la base **java markdown to pdf** bajo control. + +¡Feliz codificación, y que tus PDFs siempre se rendericen exactamente como los imaginaste! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/spanish/java/conversion-html-to-various-image-formats/_index.md b/html/spanish/java/conversion-html-to-various-image-formats/_index.md index e2fcf852e..8b1bd2f54 100644 --- a/html/spanish/java/conversion-html-to-various-image-formats/_index.md +++ b/html/spanish/java/conversion-html-to-various-image-formats/_index.md @@ -90,6 +90,8 @@ Aprenda cómo convertir HTML a GIF en Java usando Aspose.HTML. Una guía paso a Aprenda a convertir HTML a JPEG con Aspose.HTML for Java. Guía paso a paso para un procesamiento de documentos sin interrupciones. ### [Converting HTML to PNG](./convert-html-to-png/) Aprenda cómo convertir HTML a imágenes PNG en Java con Aspose.HTML. Una guía completa con instrucciones paso a paso. +### [Cómo establecer DPI – Renderizar HTML a PNG con AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Aprenda a configurar la resolución DPI al renderizar HTML a PNG usando AsposeHTML en Java. ### [Converting HTML to TIFF](./convert-html-to-tiff/) Aprenda a convertir HTML a TIFF fácilmente usando Aspose.HTML for Java. Guía paso a paso para un manejo eficiente de documentos. diff --git a/html/spanish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/spanish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..b69e2cac5 --- /dev/null +++ b/html/spanish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,227 @@ +--- +category: general +date: 2026-01-14 +description: cómo establecer dpi al convertir una URL a PNG. Aprende a renderizar + HTML a PNG, establecer el tamaño del viewport y guardar HTML como PNG usando Aspose.HTML + en Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: es +og_description: cómo establecer dpi al convertir una URL a PNG. Guía paso a paso para + renderizar HTML a PNG, controlar el tamaño del viewport y guardar HTML como PNG + usando Aspose.HTML. +og_title: Cómo establecer DPI – Renderizar HTML a PNG con AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: Cómo establecer DPI – Renderizar HTML a PNG con AsposeHTML +url: /es/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# cómo establecer dpi – Renderizar HTML a PNG con AsposeHTML + +¿Alguna vez te has preguntado **cómo establecer dpi** para una imagen similar a una captura de pantalla generada a partir de una página web? Tal vez necesites un PNG de 300 DPI para impresión, o una miniatura de baja resolución para una aplicación móvil. En cualquier caso, el truco consiste en indicar al motor de renderizado el DPI lógico que deseas, y luego dejar que haga el trabajo pesado. + +En este tutorial tomaremos una URL en vivo, la renderizaremos a un archivo PNG, **estableceremos el tamaño del viewport**, ajustaremos el DPI y, finalmente, **guardaremos HTML como PNG**—todo con Aspose.HTML para Java. Sin navegadores externos, sin herramientas complicadas de línea de comandos—solo código Java limpio que puedes incorporar a cualquier proyecto Maven o Gradle. + +> **Consejo profesional:** Si solo buscas una miniatura rápida, puedes mantener el DPI en 96 DPI (el valor predeterminado para la mayoría de pantallas). Para recursos listos para impresión, aumentalo a 300 DPI o más. + +![ejemplo de cómo establecer dpi](https://example.com/images/how-to-set-dpi.png "ejemplo de cómo establecer dpi") + +## Lo que necesitarás + +- **Java 17** (o cualquier JDK reciente). +- **Aspose.HTML for Java** 24.10 o más reciente. Puedes obtenerlo de Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Una conexión a internet para obtener la página objetivo (el ejemplo usa `https://example.com/sample.html`). +- Permiso de escritura en la carpeta de salida. + +Eso es todo—sin Selenium, sin Chrome sin cabeza. Aspose.HTML realiza el renderizado en el proceso, lo que significa que permaneces dentro de la JVM y evitas la sobrecarga de lanzar un navegador. + +## Paso 1 – Cargar el documento HTML desde una URL + +Primero creamos una instancia de `HTMLDocument` que apunta a la página que queremos capturar. El constructor descarga automáticamente el HTML, lo analiza y prepara el DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Por qué es importante:* Al cargar el documento directamente, evitas la necesidad de un cliente HTTP separado. Aspose.HTML respeta redirecciones, cookies e incluso autenticación básica si incrustas credenciales en la URL. + +## Paso 2 – Construir un sandbox con el DPI y viewport deseados + +Un **sandbox** es la forma en que Aspose.HTML imita un entorno de navegador. Aquí le indicamos que simule una pantalla de 1280 × 720 y, lo que es crucial, establecemos el **DPI del dispositivo**. Cambiar el DPI modifica la densidad de píxeles de la imagen renderizada sin alterar el tamaño lógico. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Por qué podrías ajustar estos valores:* + +- **Viewport size** controla cómo se comportan las consultas de medios CSS (`@media (max-width: …)`). +- **Device DPI** influye en el tamaño físico de la imagen al imprimir. Una imagen de 96 DPI se ve bien en pantallas; una imagen de 300 DPI mantiene la nitidez en papel. + +Si necesitas una miniatura cuadrada, simplemente cambia `setViewportSize(500, 500)` yén el DPI bajo. + +## Paso 3 – Elegir PNG como formato de salida + +Aspose.HTML admite varios formatos raster (PNG, JPEG, BMP, GIF). PNG es sin pérdida, lo que lo hace perfecto para capturas de pantalla donde deseas que cada píxel se conserve. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +También puedes ajustar el nivel de compresión (`pngOptions.setCompressionLevel(9)`) si te preocupa el tamaño del archivo. + +## Paso 4 – Renderizar y guardar la imagen + +Ahora indicamos al documento que **guarde** como una imagen. El método `save` recibe una ruta de archivo y las opciones configuradas previamente. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Cuando el programa termine, encontrarás un archivo PNG en `YOUR_DIRECTORY/sandboxed.png`. Ábrelo—si estableciste el DPI a 300, los metadatos de la imagen lo reflejarán, aunque las dimensiones en píxeles sigan siendo 1280 × 720. + +## Paso 5 – Verificar el DPI (Opcional pero útil) + +Si deseas verificar el DPI realmente se aplicó, puedes leer los metadatos PNG con una biblioteca ligera como **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Deberías ver `300` (o el valor que hayas establecido) impreso en la consola. Este paso no es necesario para el renderizado, pero es una rápida verificación, especialmente cuando generas recursos para un flujo de trabajo de impresión. + +## Preguntas comunes y casos límite + +### “¿Qué pasa si la página usa JavaScript para cargar contenido?” + +Aspose.HTML ejecuta un **subconjunto limitado** de JavaScript. Para la mayoría de los sitios estáticos funciona de inmediato. Si la página depende en gran medida de frameworks del lado del cliente (React, Angular, Vue), podrías necesitar pre‑renderizar la página o usar un navegador sin cabeza en su lugar. Sin embargo, la configuración del DPI funciona de la misma manera una vez que el DOM está listo. + +### “¿Puedo renderizar un PDF en lugar de PNG?” + +Claro. Cambia `ImageSaveOptions` por `PdfSaveOptions` y modifica la extensión de salida a `.pdf`. La configuración del DPI sigue influyendo en la apariencia rasterizada de cualquier imagen incrustada. + +### “¿Qué pasa con capturas de alta resolución para pantallas retina?” + +Simplemente duplica las dimensiones del viewport manteniendo el DPI en 96 DPI, o conserva el viewport y aumenta el DPI a 192. El PNG resultante contendrá el doble de píxeles, dándote esa nitidez característica de retina. + +### “¿Necesito limpiar los recursos?” + +`HTMLDocument` implementa `AutoCloseable`. En una aplicación de producción, envuélvelo en un bloque‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Eso garantiza que los recursos nativos se liberen rápidamente. + +## Ejemplo completo funcional (listo para copiar y pegar) + +A continuación se muestra el programa completo, listo para ejecutar. Reemplaza `YOUR_DIRECTORY` con una carpeta real en tu máquina. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Ejecuta la clase y obtendrás un PNG que respeta la configuración **cómo establecer dpi** que especificaste. + +## Conclusión + +Hemos recorrido **cómo establecer dpi** al **renderizar HTML a PNG**, cubierto el paso de **establecer el tamaño del viewport**, y te mostramos cómo **guardar HTML como PNG** usando Aspose.HTML para Java. Los puntos clave son: + +- Utiliza un **sandbox** para controlar el DPI y el viewport. +- Elige las **ImageSaveOptions** adecuadas para una salida sin pérdida. +- Verifica los metadatos DPI si necesitas garantizar la calidad de impresión. + +Desde aquí puedes experimentar con diferentes valores de DPI, viewports más grandes, o incluso procesar por lotes una lista de URLs. ¿Quieres convertir todo un sitio web en miniaturas PNG? Simplemente recorre un arreglo de URLs y reutiliza la misma configuración de sandbox. + +¡Feliz renderizado, y que tus capturas de pantalla siempre sean perfectas al píxel! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/spanish/java/css-html-form-editing/_index.md b/html/spanish/java/css-html-form-editing/_index.md index db3b14921..b85af413a 100644 --- a/html/spanish/java/css-html-form-editing/_index.md +++ b/html/spanish/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ Ahora, cambiemos de tema y exploremos cómo editar y enviar formularios HTML de Aprenda a utilizar Aspose.HTML para Java para aplicar técnicas avanzadas de CSS, incluidos márgenes de página personalizados y contenido dinámico. Un tutorial práctico y detallado para desarrolladores. ### [Edición y envío de formularios HTML con Aspose.HTML para Java](./html-form-editing/) Aprenda a editar y enviar formularios HTML mediante programación utilizando Aspose.HTML para Java en esta completa guía paso a paso. +### [Cómo obtener estilos en Java – cargar HTML y selector de consultas](./how-to-get-style-in-java-load-html-query-selector/) +Aprenda a cargar un documento HTML en Java y usar selectores de consulta para obtener estilos CSS de forma programática. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/spanish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/spanish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..90e5c2db0 --- /dev/null +++ b/html/spanish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,185 @@ +--- +category: general +date: 2026-01-14 +description: how to get style in Java – learn how to load HTML document, use a query + selector example, and read the background-color property with Aspose.HTML. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: es +og_description: how to get style in Java – step‑by‑step guide to load an HTML document, + run a query selector example, and fetch the background-color property. +og_title: how to get style in Java – load HTML & query selector +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: how to get style in Java – load HTML & query selector +url: /es/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# cómo obtener estilo en Java – cargar HTML y selector de consultas + +¿Alguna vez te has preguntado **cómo obtener el estilo** de un elemento mientras analizas HTML con Java? Tal vez estés creando un scraper, una herramienta de pruebas, o simplemente necesites verificar indicios visuales en una página generada. La buena noticia es que Aspose.HTML lo hace muy sencillo. En este tutorial recorreremos la carga de un documento HTML, usando un **ejemplo de selector de consultas**, y finalmente leyendo la **propiedad background-color** de un elemento `
`. Sin trucos, solo código Java claro que puedes copiar‑pegar y ejecutar. + +## Lo que necesitarás + +Antes de comenzar, asegúrate de tener: + +* **Java 17** (o cualquier JDK reciente) – la API funciona con Java 8+ pero las versiones más nuevas ofrecen mejor rendimiento. +* Biblioteca **Aspose.HTML for Java** – puedes obtenerla desde Maven Central (`com.aspose:aspose-html:23.10` al momento de escribir). +* Un pequeño archivo HTML (`input.html`) que contenga al menos un `
` con un `background‑color` definido ya sea en línea o mediante una hoja de estilos. + +Eso es todo. Sin frameworks adicionales, sin navegadores pesados, solo Java puro y Aspose.HTML. + +## Paso 1: Cargar el documento HTML + +Lo primero que debes hacer es **cargar el documento html** en memoria. La clase `HTMLDocument` de Aspose.HTML abstrae el manejo del sistema de archivos y te brinda un DOM que puedes consultar. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Por qué es importante:** Cargar el documento crea un árbol DOM analizado, que es la base para cualquier evaluación posterior de CSS o JavaScript. Si el archivo no se encuentra, Aspose lanza una `FileNotFoundException` descriptiva, así que verifica la ruta. + +### Consejo profesional +Si estás obteniendo HTML desde una URL en lugar de un archivo, simplemente pasa la cadena de la URL al constructor – Aspose gestiona la solicitud HTTP por ti. + +## Paso 2: Usar un ejemplo de selector de consultas + +Ahora que el documento está en memoria, vamos a **usar un ejemplo de selector de consultas** para obtener el primer elemento `
`. El método `querySelector` replica la sintaxis de selectores CSS que ya conoces del navegador. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Por qué es importante:** `querySelector` devuelve el primer nodo que coincide, lo que es perfecto cuando solo necesitas el estilo de un único elemento. Si necesitas varios elementos, `querySelectorAll` devuelve un `NodeList`. + +### Caso límite +Si el selector no coincide con nada, `divElement` será `null`. Siempre protege contra eso antes de intentar leer estilos: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Paso 3: Obtener el estilo computado + +Con el elemento en mano, el siguiente paso es **analizar html java** lo suficiente para calcular los valores finales de CSS. Aspose.HTML hace el trabajo pesado: resuelve la cascada, la herencia e incluso hojas de estilo externas. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Por qué es importante:** El estilo computado refleja los valores exactos que el navegador aplicaría después de procesar todas las reglas CSS. Es más fiable que leer el atributo `style` crudo, que puede estar incompleto. + +## Paso 4: Recuperar la propiedad background‑color + +Finalmente, extraemos la **propiedad background-color** que nos interesa. El método `getPropertyValue` devuelve el valor como una cadena (p. ej., `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Lo que verás:** Si tu `
` tenía `background-color: #ff5733;` ya sea en línea o mediante una hoja de estilo, la consola mostrará algo como `Computed background‑color: rgb(255, 87, 51)`. + +### Trampa común +Cuando la propiedad no está definida, `getPropertyValue` devuelve una cadena vacía. Eso es una señal para usar un valor predeterminado o inspeccionar los estilos del elemento padre. + +## Ejemplo completo y funcional + +Juntándolo todo, aquí tienes el programa completo, listo para ejecutar: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Salida esperada (ejemplo):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Si el `
` no tiene color de fondo definido, la salida será una línea vacía – esa es tu señal para revisar los estilos heredados. + +## Consejos, trucos y cosas a tener en cuenta + +| Situación | Qué hacer | +|-----------|-----------| +| **Múltiples elementos `
`** | Usa `querySelectorAll("div")` y recorre el `NodeList`. | +| **Archivos CSS externos** | Asegúrate de que el archivo HTML los referencie con rutas correctas; Aspose.HTML los obtendrá automáticamente. | +| **Solo atributo `style` en línea** | `getComputedStyle` sigue funcionando – combina estilos en línea con los predeterminados. | +| **Preocupaciones de rendimiento** | Carga el documento una sola vez, reutiliza el objeto `HTMLDocument` si necesitas consultar muchos elementos. | +| **Ejecutar en Android** | Aspose.HTML for Java soporta Android, pero deberás incluir el AAR específico para Android. | + +## Temas relacionados que podrías explorar + +* **Parsing HTML with Jsoup vs. Aspose.HTML** – cuándo elegir uno sobre el otro. +* **Exportar estilos computados a JSON** – útil para front‑ends impulsados por API. +* **Automatizar generación de capturas de pantalla** – combina estilos computados con Aspose.PDF para pruebas de regresión visual. + +--- + +### Conclusión + +Ahora sabes **cómo obtener el estilo** de cualquier elemento cuando **cargas el documento html** con Aspose.HTML, ejecutas un **ejemplo de selector de consultas**, y extraes la **propiedad background-color**. El código es autónomo, funciona en cualquier JDK reciente y maneja de forma elegante los elementos ausentes o los estilos no definidos. Desde aquí puedes ampliar el enfoque para obtener tamaños de fuente, márgenes, o incluso valores computados después de la ejecución de JavaScript (Aspose.HTML también soporta evaluación de scripts). + +¡Pruébalo, ajusta el selector y descubre qué otros tesoros CSS puedes revelar. ¡Feliz codificación! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/swedish/java/conversion-html-to-various-image-formats/_index.md b/html/swedish/java/conversion-html-to-various-image-formats/_index.md index b0924dbce..355d320b8 100644 --- a/html/swedish/java/conversion-html-to-various-image-formats/_index.md +++ b/html/swedish/java/conversion-html-to-various-image-formats/_index.md @@ -88,15 +88,11 @@ Att använda Aspose.HTML for Java förenklar konverteringen av HTML‑dokument t ## Konvertering – HTML till olika bildformat – Handledningar ### [Konvertera HTML till BMP](./convert-html-to-bmp/) -Konvertera HTML till BMP med Aspose.HTML for Java. En omfattande handledning för att sömlöst omvandla HTML‑dokument till BMP‑bilder med Aspose.HTML for Java. ### [Konvertera HTML till GIF](./convert-html-to-gif/) -Lär dig hur du konverterar HTML till GIF i Java med Aspose.HTML. En komplett steg‑för‑steg‑guide för effektiv HTML‑till‑GIF‑konvertering. ### [Konvertera HTML till JPEG](./convert-html-to-jpeg/) -Lär dig konvertera HTML till JPEG med Aspose.HTML for Java. Steg‑för‑steg‑guide för smidig dokumentbehandling. ### [Konvertera HTML till PNG](./convert-html-to-png/) -Lär dig hur du konverterar HTML till PNG‑bilder i Java med Aspose.HTML. En omfattande guide med detaljerade instruktioner. +### [Ställ in DPI – Rendera HTML till PNG med AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) ### [Konvertera HTML till TIFF](./convert-html-to-tiff/) -Lär dig enkelt konvertera HTML till TIFF med Aspose.HTML for Java. Steg‑för‑steg‑guide för effektiv dokumenthantering. ## Vanliga frågor diff --git a/html/swedish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/swedish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..f1e844e76 --- /dev/null +++ b/html/swedish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: hur man ställer in dpi när man konverterar en URL till PNG. Lär dig rendera + HTML till PNG, ställa in viewport‑storlek och spara HTML som PNG med Aspose.HTML + i Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: sv +og_description: hur man ställer in dpi när man konverterar en URL till PNG. Steg‑för‑steg‑guide + för att rendera HTML till PNG, kontrollera viewport‑storlek och spara HTML som PNG + med Aspose.HTML. +og_title: hur man ställer in dpi – Rendera HTML till PNG med AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: hur man ställer in dpi – Rendera HTML till PNG med AsposeHTML +url: /sv/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# hur man ställer in dpi – Rendera HTML till PNG med AsposeHTML + +Har du någonsin undrat **hur man ställer in dpi** för en skärmbild‑liknande bild som genereras från en webbsida? Kanske behöver du en 300 DPI PNG för utskrift, eller en låg‑upplöst miniatyr för en mobilapp. I båda fallen är tricket att tala om för renderingsmotorn vilken logisk DPI du vill ha, och sedan låta den göra det tunga arbetet. + +I den här handledningen tar vi en live‑URL, renderar den till en PNG‑fil, **ställer in viewport‑storleken**, justerar DPI, och slutligen **sparar HTML som PNG**—allt med Aspose.HTML för Java. Inga externa webbläsare, inga röriga kommandoradsverktyg—bara ren Java‑kod som du kan lägga in i vilket Maven‑ eller Gradle‑projekt som helst. + +> **Pro tip:** Om du bara vill ha en snabb miniatyr kan du behålla DPI på 96 DPI (standard för de flesta skärmar). För utskriftsklara resurser, höj den till 300 DPI eller högre. + +![exempel på hur man ställer in dpi](https://example.com/images/how-to-set-dpi.png "exempel på hur man ställer in dpi") + +## Vad du behöver + +- **Java 17** (eller någon nyare JDK). +- **Aspose.HTML for Java** 24.10 eller nyare. Du kan hämta den från Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- En internetanslutning för att hämta målsidan (exemplet använder `https://example.com/sample.html`). +- Skrivrättigheter till utdata‑mappen. + +Det är allt—ingen Selenium, ingen headless Chrome. Aspose.HTML gör renderingen i‑process, vilket betyder att du stannar inom JVM och undviker overheaden av att starta en webbläsare. + +## Steg 1 – Ladda HTML‑dokumentet från en URL + +Först skapar vi en `HTMLDocument`‑instans som pekar på sidan vi vill fånga. Konstruktorn laddar automatiskt ner HTML, parsar den och förbereder DOM‑en. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Varför detta är viktigt:* Genom att ladda dokumentet direkt hoppar du över behovet av en separat HTTP‑klient. Aspose.HTML respekterar omdirigeringar, cookies och även grundläggande autentisering om du bäddar in referenser i URL‑en. + +## Steg 2 – Bygg en sandbox med önskad DPI och viewport + +En **sandbox** är Aspose.HTML:s sätt att efterlikna en webbläsarmiljö. Här får vi den att låtsas vara en 1280 × 720‑skärm och, avgörande, vi ställer in **device DPI**. Att ändra DPI förändrar bildens pixeldensitet utan att ändra den logiska storleken. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Varför du kan vilja justera dessa värden:* +- **Viewport‑storlek** styr hur CSS‑media‑queries (`@media (max-width: …)`) beter sig. +- **Device DPI** påverkar den fysiska storleken på bilden när den skrivs ut. En 96 DPI‑bild ser bra ut på skärmar; en 300 DPI‑bild behåller skärpan på papper. + +Om du behöver en fyrkantig miniatyr, ändra helt enkelt `setViewportSize(500, 500)` och håll DPI låg. + +## Steg 3 – Välj PNG som utdataformat + +Aspose.HTML stödjer flera rasterformat (PNG, JPEG, BMP, GIF). PNG är förlustfri, vilket gör den perfekt för skärmbilder där du vill ha varje pixel bevarad. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Du kan också justera komprimeringsnivån (`pngOptions.setCompressionLevel(9)`) om du är orolig för filstorleken. + +## Steg 4 – Rendera och spara bilden + +Nu instruerar vi dokumentet att **spara** sig själv som en bild. `save`‑metoden tar en filsökväg och de tidigare konfigurerade alternativen. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +När programmet är klart hittar du en PNG‑fil på `YOUR_DIRECTORY/sandboxed.png`. Öppna den—om du har ställt in DPI till 300 kommer bildmetadata att återspegla det, även om pixelmåtten fortfarande är 1280 × 720. + +## Steg 5 – Verifiera DPI (valfritt men praktiskt) + +Om du vill dubbelkolla att DPI verkligen har tillämpats kan du läsa PNG‑metadata med ett lättviktigt bibliotek som **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Du bör se `300` (eller vad du än har angett) skrivet till konsolen. Detta steg krävs inte för rendering, men det är en snabb kontroll, särskilt när du genererar resurser för ett utskriftsflöde. + +## Vanliga frågor & kantfall + +### ”Vad händer om sidan använder JavaScript för att ladda innehåll?” + +Aspose.HTML kör ett **begränsat delmängd** av JavaScript. För de flesta statiska webbplatser fungerar det direkt. Om sidan starkt förlitar sig på klient‑side‑ramverk (React, Angular, Vue) kan du behöva för‑rendera sidan eller använda en headless‑browser istället. DPI‑inställningen fungerar dock på samma sätt när DOM‑en är klar. + +### ”Kan jag rendera en PDF istället för PNG?” + +Absolut. Byt `ImageSaveOptions` mot `PdfSaveOptions` och ändra utdata‑filändelsen till `.pdf`. DPI‑inställningen påverkar fortfarande det rasteriserade utseendet på eventuella inbäddade bilder. + +### ”Vad gäller högupplösta skärmbilder för retina‑skärmar?” + +Dubbel helt enkelt viewport‑dimensionerna samtidigt som du behåller DPI på 96 DPI, eller behåll viewporten och höj DPI till 192. Den resulterande PNG‑filen kommer att innehålla dubbelt så många pixlar, vilket ger den skarpa retina‑känslan. + +### ”Behöver jag rensa resurser?” + +`HTMLDocument` implementerar `AutoCloseable`. I en produktionsapp, omslut den i ett try‑with‑resources‑block: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Det säkerställer att inhemska resurser frigörs omedelbart. + +## Fullt fungerande exempel (klar att kopiera‑klistra in) + +Nedan är det kompletta, klar‑att‑köra‑programmet. Ersätt `YOUR_DIRECTORY` med en faktisk mapp på din maskin. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Kör klassen, så får du en PNG som respekterar **hur man ställer in dpi**‑inställningen du angav. + +## Slutsats + +Vi har gått igenom **hur man ställer in dpi** när du **renderar HTML till PNG**, täckt steget **set viewport size**, och visat hur du **sparar HTML som PNG** med Aspose.HTML för Java. De viktigaste slutsatserna är: + +- Använd en **sandbox** för att kontrollera DPI och viewport. +- Välj rätt **ImageSaveOptions** för förlustfri utdata. +- Verifiera DPI‑metadata om du behöver garantera utskriftskvalitet. + +Härifrån kan du experimentera med olika DPI‑värden, större viewports, eller till och med batch‑processa en lista med URL:er. Vill du konvertera en hel webbplats till PNG‑miniatyrer? Loopa bara över en array med URL:er och återanvänd samma sandbox‑konfiguration. + +Lycka till med rendering, och må dina skärmbilder alltid vara pixel‑perfekta! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/thai/java/conversion-html-to-various-image-formats/_index.md b/html/thai/java/conversion-html-to-various-image-formats/_index.md index 3217a010e..775f78eb7 100644 --- a/html/thai/java/conversion-html-to-various-image-formats/_index.md +++ b/html/thai/java/conversion-html-to-various-image-formats/_index.md @@ -95,6 +95,7 @@ weight: 24 เรียนรู้วิธีการแปลง HTML เป็น JPEG ด้วย Aspose.HTML สำหรับ Java คู่มือทีละขั้นตอนสำหรับการประมวลผลเอกสารอย่างราบรื่น ### [การแปลง HTML เป็น PNG](./convert-html-to-png/) เรียนรู้วิธีการแปลง HTML เป็นภาพ PNG ใน Java ด้วย Aspose.HTML คู่มือฉบับสมบูรณ์พร้อมคำแนะนำทีละขั้นตอน +### [วิธีตั้งค่า DPI – เรนเดอร์ HTML เป็น PNG ด้วย AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) ### [การแปลง HTML เป็น TIFF](./convert-html-to-tiff/) เรียนรู้วิธีการแปลง HTML เป็น TIFF ได้อย่างง่ายดายโดยใช้ Aspose.HTML สำหรับ Java คู่มือทีละขั้นตอนเพื่อการจัดการเอกสารอย่างมีประสิทธิภาพ diff --git a/html/thai/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/thai/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..46893af27 --- /dev/null +++ b/html/thai/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,224 @@ +--- +category: general +date: 2026-01-14 +description: วิธีตั้งค่า DPI เมื่อแปลง URL เป็น PNG เรียนรู้การแปลง HTML เป็น PNG + ตั้งค่าขนาด viewport และบันทึก HTML เป็น PNG ด้วย Aspose.HTML ใน Java +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: th +og_description: วิธีตั้งค่า DPI เมื่อแปลง URL เป็น PNG. คู่มือขั้นตอนต่อขั้นตอนในการเรนเดอร์ + HTML เป็น PNG, ควบคุมขนาด viewport, และบันทึก HTML เป็น PNG ด้วย Aspose.HTML. +og_title: วิธีตั้งค่า DPI – แปลง HTML เป็น PNG ด้วย AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: วิธีตั้งค่า DPI – แปลง HTML เป็น PNG ด้วย AsposeHTML +url: /th/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# วิธีตั้งค่า DPI – แปลง HTML เป็น PNG ด้วย AsposeHTML + +เคยสงสัย **วิธีตั้งค่า DPI** สำหรับภาพที่คล้ายกับสกรีนช็อตที่สร้างจากหน้าเว็บหรือไม่? บางครั้งคุณอาจต้องการ PNG 300 DPI สำหรับการพิมพ์, หรือภาพขนาดเล็กความละเอียดต่ำสำหรับแอปมือถือ. ไม่ว่ากรณีใดก็ตาม เทคนิคคือบอกเครื่องมือเรนเดอร์ว่าต้องการ DPI เชิงตรรกะเท่าใด, แล้วให้มันทำงานหนักให้เอง. + +ในบทแนะนำนี้เราจะใช้ URL สด, แปลงเป็นไฟล์ PNG, **ตั้งค่าขนาด viewport**, ปรับ DPI, และสุดท้าย **บันทึก HTML เป็น PNG**—ทั้งหมดด้วย Aspose.HTML for Java. ไม่ต้องใช้เบราว์เซอร์ภายนอก, ไม่ต้องใช้เครื่องมือบรรทัดคำสั่งที่ยุ่งยาก—แค่โค้ด Java สะอาดที่คุณสามารถใส่ลงในโปรเจกต์ Maven หรือ Gradle ใดก็ได้. + +> **เคล็ดลับ:** หากคุณต้องการเพียงภาพขนาดย่ออย่างรวดเร็ว, สามารถคง DPI ที่ 96 DPI (ค่าเริ่มต้นสำหรับหน้าจอส่วนใหญ่). สำหรับสินค้าที่พร้อมพิมพ์, เพิ่มเป็น 300 DPI หรือสูงกว่า. + +![ตัวอย่างการตั้งค่า DPI](https://example.com/images/how-to-set-dpi.png "ตัวอย่างการตั้งค่า DPI") + +## สิ่งที่คุณต้องเตรียม + +- **Java 17** (หรือ JDK รุ่นใหม่ใดก็ได้). +- **Aspose.HTML for Java** 24.10 หรือใหม่กว่า. คุณสามารถดาวน์โหลดได้จาก Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- การเชื่อมต่ออินเทอร์เน็ตเพื่อดึงหน้าที่ต้องการ (ตัวอย่างใช้ `https://example.com/sample.html`). +- สิทธิ์การเขียนในโฟลเดอร์ปลายทาง. + +เท่านี้—ไม่ต้อง Selenium, ไม่ต้อง Chrome แบบ headless. Aspose.HTML ทำการเรนเดอร์ภายในกระบวนการ, ซึ่งหมายความว่าคุณจะอยู่ใน JVM ตลอดและหลีกเลี่ยงค่าใช้จ่ายของการเปิดเบราว์เซอร์. + +## ขั้นตอน 1 – โหลดเอกสาร HTML จาก URL + +ก่อนอื่นเราจะสร้างอินสแตนซ์ `HTMLDocument` ที่ชี้ไปยังหน้าเว็บที่ต้องการจับภาพ. คอนสตรัคเตอร์จะดาวน์โหลด HTML โดยอัตโนมัติ, แยกวิเคราะห์, และเตรียม DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*เหตุผลที่สำคัญ:* การโหลดเอกสารโดยตรงทำให้คุณไม่ต้องใช้ HTTP client แยกต่างหาก. Aspose.HTML รองรับการเปลี่ยนเส้นทาง, คุกกี้, และแม้กระทั่งการยืนยันตัวตนพื้นฐานหากคุณฝังข้อมูลประจำตัวใน URL. + +## ขั้นตอน 2 – สร้าง Sandbox ด้วย DPI และ Viewport ที่ต้องการ + +**Sandbox** คือวิธีของ Aspose.HTML ที่จำลองสภาพแวดล้อมของเบราว์เซอร์. ที่นี่เราบอกให้มันทำตัวเหมือนหน้าจอ 1280 × 720 และสำคัญที่สุด, เราตั้งค่า **device DPI**. การเปลี่ยน DPI จะเปลี่ยนความหนาแน่นพิกเซลของภาพที่เรนเดโดยไม่กระทบขนาดเชิงตรรกะ. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*เหตุผลที่คุณอาจปรับค่าเหล่านี้:* +- **ขนาด viewport** ควบคุมการทำงานของ media query ของ CSS (`@media (max-width: …)`). +- **Device DPI** มีผลต่อขนาดภาพจริงเมื่อพิมพ์. ภาพ 96 DPI ดูดีบนหน้าจอ; ภาพ 300 DPI จะคมชัดบนกระดาษ. + +หากต้องการภาพขนาดย่อสี่เหลี่ยมจัตุรัส, เพียงเปลี่ยน `setViewportSize(500, 500)` และคง DPI ต่ำไว้. + +## ขั้นตอน 3 – เลือก PNG เป็นรูปแบบผลลัพธ์ + +Aspose.HTML รองรับหลายรูปแบบเรสเตอร์ (PNG, JPEG, BMP, GIF). PNG เป็นแบบ loss‑less, ทำให้เหมาะกับสกรีนช็อตที่ต้องการรักษาพิกเซลทุกจุด. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +คุณยังสามารถปรับระดับการบีบอัด (`pngOptions.setCompressionLevel(9)`) หากกังวลเรื่องขนาดไฟล์. + +## ขั้นตอน 4 – เรนเดอร์และบันทึกภาพ + +ตอนนี้เราบอกเอกสารให้ **บันทึก** ตัวเองเป็นภาพ. เมธอด `save` รับพาธไฟล์และตัวเลือกที่กำหนดไว้ก่อนหน้า. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +เมื่อโปรแกรมทำงานเสร็จ, คุณจะพบไฟล์ PNG ที่ `YOUR_DIRECTORY/sandboxed.png`. เปิดไฟล์—หากคุณตั้งค่า DPI เป็น 300, เมตาดาต้าของภาพจะแสดงค่า DPI นั้น, แม้ว่าขนาดพิกเซลจะยังคงเป็น 1280 × 720. + +## ขั้นตอน 5 – ตรวจสอบ DPI (ไม่บังคับแต่แนะนำ) + +หากต้องการตรวจสอบว่าการตั้งค่า DPI ถูกนำไปใช้จริงหรือไม่, คุณสามารถอ่านเมตาดาต้า PNG ด้วยไลบรารีขนาดเล็กอย่าง **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +คุณควรเห็นค่า `300` (หรือค่าที่คุณตั้ง) แสดงบนคอนโซล. ขั้นตอนนี้ไม่จำเป็นสำหรับการเรนเดอร์, แต่เป็นการตรวจสอบอย่างรวดเร็วโดยเฉพาะเมื่อคุณสร้างสินค้าสำหรับกระบวนการพิมพ์. + +## คำถามที่พบบ่อย & กรณีขอบ + +### “ถ้าหน้าเว็บใช้ JavaScript โหลดเนื้อหา?” + +Aspose.HTML ทำงานกับ **ส่วนย่อยของ JavaScript** ที่จำกัด. สำหรับเว็บไซต์สแตติกส่วนใหญ่จะทำงานได้ทันที. หากหน้าเว็บพึ่งพาเฟรมเวิร์กฝั่งคลไอเอนท์ (React, Angular, Vue) อย่างหนัก, คุณอาจต้องทำการ pre‑render หน้าเว็บหรือใช้ headless browser แทน. อย่างไรก็ตาม, การตั้งค่า DPI จะทำงานเช่นเดิมเมื่อ DOM พร้อม. + +### “ฉันสามารถเรนเดอร์เป็น PDF แทน PNG ได้ไหม?” + +ทำได้แน่นอน. แทนที่ `ImageSaveOptions` ด้วย `PdfSaveOptions` และเปลี่ยนนามสกุลไฟล์เป็น `.pdf`. การตั้งค่า DPI ยังมีผลต่อการแสดงผลแบบ raster ของภาพที่ฝังอยู่ใน PDF. + +### “ต้องการสกรีนช็อตความละเอียดสูงสำหรับหน้าจอ Retina?” + +เพียงเพิ่มสองเท่าของขนาด viewport พร้อมคง DPI ที่ 96 DPI, หรือคง viewport เดิมแล้วเพิ่ม DPI เป็น 192. PNG ที่ได้จะมีพิกเซลสองเท่า, ให้ความคมชัดแบบ Retina. + +### “ต้องทำความสะอาดทรัพยากรหรือไม่?” + +`HTMLDocument` implements `AutoCloseable`. ในแอปพลิเคชันจริง, ควรห่อไว้ในบล็อก try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +วิธีนี้จะทำให้ทรัพยากรเนทีฟถูกปล่อยอย่างทันท่วงที. + +## ตัวอย่างทำงานเต็มรูปแบบ (พร้อมคัดลอก‑วาง) + +ด้านล่างเป็นโปรแกรมที่สมบูรณ์พร้อมรัน. แทนที่ `YOUR_DIRECTORY` ด้วยโฟลเดอร์จริงบนเครื่องของคุณ. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +รันคลาสและคุณจะได้ PNG ที่เคารพการ **ตั้งค่า DPI** ที่คุณกำหนดไว้. + +## สรุป + +เราได้อธิบาย **วิธีตั้งค่า DPI** เมื่อ **เรนเดอร์ HTML เป็น PNG**, ครอบคลุมขั้นตอน **ตั้งค่าขนาด viewport** และแสดงวิธี **บันทึก HTML เป็น PNG** ด้วย Aspose.HTML for Java. จุดสำคัญที่ควรจำคือ: + +- ใช้ **sandbox** เพื่อควบคุม DPI และ viewport. +- เลือก **ImageSaveOptions** ที่เหมาะสำหรับผลลัพธ์ lossless. +- ตรวจสอบเมตาดาต้า DPI หากต้องการรับประกันคุณภาพการพิมพ์. + +ต่อจากนี้คุณสามารถทดลองกับค่า DPI ต่าง ๆ, viewport ที่ใหญ่ขึ้น, หรือแม้กระทั่งประมวลผลหลาย URL พร้อมกัน. อยากแปลงเว็บไซต์ทั้งหมดเป็นภาพย่อ PNG? เพียงวนลูปอาร์เรย์ของ URL แล้วใช้การตั้งค่า sandbox เดียวกัน. + +ขอให้การเรนเดอร์ของคุณสนุกและภาพสกรีนช็อตของคุณเต็มไปด้วยพิกเซลที่สมบูรณ์แบบ! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/turkish/java/conversion-html-to-various-image-formats/_index.md b/html/turkish/java/conversion-html-to-various-image-formats/_index.md index 5b1d4e93f..1f87bbe88 100644 --- a/html/turkish/java/conversion-html-to-various-image-formats/_index.md +++ b/html/turkish/java/conversion-html-to-various-image-formats/_index.md @@ -98,6 +98,8 @@ Aspose.HTML for Java ile HTML'yi JPEG'ye dönüştürmeyi öğrenin. Sorunsuz be Aspose.HTML ile Java'da HTML'yi PNG görüntülerine dönüştürmeyi öğrenin. Kapsamlı bir rehber ve adım‑adım talimatlar. ### [HTML'yi TIFF'ye Dönüştürme](./convert-html-to-tiff/) Aspose.HTML for Java kullanarak HTML'yi TIFF'ye kolayca dönüştürmeyi öğrenin. Verimli belge işleme için adım‑adım bir rehber. +### [DPI ayarlama – AsposeHTML ile HTML'yi PNG'ye render et](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Aspose.HTML for Java kullanarak PNG çıktısının DPI değerini nasıl ayarlayacağınızı öğrenin. ## Sıkça Sorulan Sorular diff --git a/html/turkish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/turkish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..fab234dc1 --- /dev/null +++ b/html/turkish/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,226 @@ +--- +category: general +date: 2026-01-14 +description: Bir URL'yi PNG'ye dönüştürürken DPI nasıl ayarlanır. HTML'yi PNG'ye render + etmeyi, görünüm alanı boyutunu ayarlamayı ve Aspose.HTML'i Java'da kullanarak HTML'yi + PNG olarak kaydetmeyi öğrenin. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: tr +og_description: Bir URL'yi PNG'ye dönüştürürken DPI nasıl ayarlanır. HTML'yi PNG'ye + render etme, görünüm alanı boyutunu kontrol etme ve Aspose.HTML kullanarak HTML'yi + PNG olarak kaydetme adım adım rehberi. +og_title: dpi nasıl ayarlanır – AsposeHTML ile HTML'yi PNG'ye dönüştür +tags: +- AsposeHTML +- Java +- image rendering +title: dpi nasıl ayarlanır – AsposeHTML ile HTML'yi PNG'ye dönüştürme +url: /tr/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# dpi nasıl ayarlanır – AsposeHTML ile HTML'yi PNG'ye Render Etme + +Web sayfasından oluşturulan ekran görüntüsü benzeri bir görüntünün **dpi nasıl ayarlanır** merak ettiniz mi? Belki baskı için 300 DPI PNG'ye, ya da mobil uygulama için düşük çözünürlüklü bir küçük resme ihtiyacınız var. Hangi durumda olursanız olun, püf noktası, render motoruna istediğiniz mantıksal DPI'yi söylemek ve ardından işin geri kalanını ona bırakmaktır. + +Bu öğreticide canlı bir URL alıp onu PNG dosyasına render edeceğiz, **görüntü alanı boyutunu ayarlayacağız**, DPI'yi değiştireceğiz ve sonunda **HTML'yi PNG olarak kaydedeceğiz**—hepsi Aspose.HTML for Java ile. Harici tarayıcılar yok, karmaşık komut satırı araçları yok—herhangi bir Maven ya da Gradle projesine ekleyebileceğiniz temiz Java kodu. + +> **Pro ipucu:** Sadece hızlı bir küçük resim istiyorsanız DPI'yi 96 DPI (çoğu ekranın varsayılanı) olarak bırakabilirsiniz. Baskıya hazır varlıklar için DPI'yi 300 DPI ya da daha yüksek bir değere çıkarın. + +![dpi ayarlama örneği](https://example.com/images/how-to-set-dpi.png "dpi ayarlama örneği") + +## Gerekenler + +- **Java 17** (veya daha yeni bir JDK). +- **Aspose.HTML for Java** 24.10 veya daha yeni bir sürüm. Maven Central'dan alabilirsiniz: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Hedef sayfayı indirmek için bir internet bağlantısı (örnek `httpsexample.com/sample.html` adresini kullanıyor). +- Çıktı klasörüne yazma izni. + +Hepsi bu—Selenium yok, headless Chrome yok. Aspose.HTML render işlemini süreç içinde yapar, yani JVM içinde kalırsınız ve bir tarayıcı başlatmanın getirdiği yükten kaçınırsınız. + +## Adım 1 – URL'den HTML Belgesini Yükleme + +İlk olarak yakalamak istediğimiz sayfayı işaret eden bir `HTMLDocument` örneği oluşturuyoruz. Yapıcı otomatik olarak HTML'i indirir, ayrıştırır ve DOM'u hazırlar. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Bu neden önemli:* Belgeyi doğrudan yükleyerek ayrı bir HTTP istemcisine ihtiyaç duymamış olursunuz. Aspose.HTML yönlendirmeleri, çerezleri ve hatta URL içinde kimlik bilgileri gömülü ise temel kimlik doğrulamayı da destekler. + +## Adım 2 – İstenen DPI ve Görüntü Alanı ile Sandbox Oluşturma + +Bir **sandbox**, Aspose.HTML'in bir tarayıcı ortamını taklit etme şeklidir. Burada ona 1280 × 720 ekran olduğunu ve kritik olarak **cihaz DPI'sini** ayarladığımızı söylüyoruz. DPI'yi değiştirmek, mantıksal boyutu etkilemeden render edilen görüntünün piksel yoğunluğunu değiştirir. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Bu değerleri neden ayarlayabilirsiniz:* +- **Viewport size** CSS medya sorgularının (`@media (max-width: …)`) nasıl davranacağını kontrol eder. +- **Device DPI** görüntünün baskı sırasında fiziksel boyutunu etkiler. 96 DPI bir görüntü ekranda iyi görünür; 300 DPI bir görüntü ise kağıtta keskinliğini korur. + +Kare bir küçük resme ihtiyacınız varsa sadece `setViewportSize(500, 500)` değiştirin ve DPI'yi düşük tutun. + +## Adım 3 – Çıktı Formatı Olarak PNG Seçme + +Aspose.HTML birkaç raster formatını destekler (PNG, JPEG, BMP, GIF). PNG kayıpsızdır, bu da her pikselin korunmasını istediğiniz ekran görüntüleri için mükemmeldir. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Dosya boyutu konusunda endişeniz varsa sıkıştırma seviyesini (`pngOptions.setCompressionLevel(9)`) de ayarlayabilirsiniz. + +## Adım 4 – Görüntüyü Render Et ve Kaydet + +Şimdi belgeye kendisini bir görüntü olarak **kaydet**mesini söylüyoruz. `save` metodu bir dosya yolu ve önceden yapılandırılmış seçenekleri alır. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Program bittiğinde `YOUR_DIRECTORY/sandboxed.png` konumunda bir PNG dosyası bulacaksınız. Açın—DPI'yi 300 olarak ayarladıysanız, görüntü meta verileri bunu yansıtacak, piksel boyutları ise 1280 × 720 olarak kalacaktır. + +## Adım 5 – DPI'yi Doğrulama (Opsiyonel ama Kullanışlı) + +DPI'nin gerçekten uygulandığını iki kez kontrol etmek isterseniz, **metadata‑extractor** gibi hafif bir kütüphane ile PNG meta verilerini okuyabilirsiniz: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Konsolda `300` (veya ayarladığınız değer) yazdırıldığını görmelisiniz. Bu adım render için zorunlu değildir, ancak baskı iş akışı için varlıklar üretirken hızlı bir doğrulama sağlar. + +## Yaygın Sorular ve Kenar Durumları + +### “Sayfa içeriği yüklemek için JavaScript kullanıyorsa ne olur?” + +Aspose.HTML **sınırlı bir alt küme** JavaScript çalıştırır. Çoğu statik site için kutudan çıkar çıkmaz çalışır. Sayfa, istemci tarafı framework'lerine (React, Angular, Vue) yoğun bir şekilde bağımlıysa, sayfayı önceden render etmeniz ya da bir headless tarayıcı kullanmanız gerekebilir. Ancak DOM hazır olduğunda DPI ayarı aynı şekilde çalışır. + +### “PNG yerine PDF render edebilir miyim?” + +Kesinlikle. `ImageSaveOptions` yerine `PdfSaveOptions` kullanın ve çıktı uzantısını `.pdf` olarak değiştirin. DPI ayarı, gömülü görüntülerin rasterleştirilmiş görünümünü hâlâ etkiler. + +### “Retina ekranlar için yüksek çözünürlüklü ekran görüntüleri ne yapmalı?” + +Viewport boyutlarını iki katına çıkarın ve DPI'yi 96 DPI tutun, ya da viewport'u aynı tutup DPI'yi 192'ye çıkarın. Ortaya çıkan PNG iki kat daha fazla piksel içerecek ve retina hissini sağlayacaktır. + +### “Kaynakları temizlemem gerekiyor mu?” + +`HTMLDocument` `AutoCloseable` uygular. Üretim uygulamasında bunu bir try‑with‑resources bloğuna sarın: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Bu, yerel kaynakların hızlı bir şekilde serbest bırakılmasını sağlar. + +## Tam Çalışan Örnek (Kopyala‑Yapıştır Hazır) + +Aşağıda eksiksiz, çalıştırmaya hazır program yer alıyor. `YOUR_DIRECTORY` ifadesini makinenizdeki gerçek bir klasörle değiştirin. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Sınıfı çalıştırın, ve belirttiğiniz **dpi nasıl ayarlanır** ayarını koruyan bir PNG elde edeceksiniz. + +## Sonuç + +**dpi nasıl ayarlanır** konusunu **HTML'yi PNG'ye render ederken**, **görüntü alanı boyutunu ayarlama** adımını ele alarak ve Aspose.HTML for Java kullanarak **HTML'yi PNG olarak kaydetme** sürecini gösterdik. Özetle: + +- DPI ve viewport kontrolü için bir **sandbox** kullanın. +- Kayıpsız çıktı için doğru **ImageSaveOptions** seçin. +- Baskı kalitesini garanti altına almak istiyorsanız DPI meta verisini doğrulayın. + +Buradan farklı DPI değerleri, daha büyük viewport'lar deneyebilir ya da URL listelerini toplu işleyebilirsiniz. Tüm bir web sitesini PNG küçük resimlerine dönüştürmek mi istiyorsunuz? URL dizisini döngüye alın ve aynı sandbox yapılandırmasını yeniden kullanın. + +Keyifli renderlar, ve ekran görüntüleriniz her zaman piksel‑kusursuz olsun! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/turkish/java/css-html-form-editing/_index.md b/html/turkish/java/css-html-form-editing/_index.md index 273930fbb..6b309abc9 100644 --- a/html/turkish/java/css-html-form-editing/_index.md +++ b/html/turkish/java/css-html-form-editing/_index.md @@ -30,9 +30,12 @@ Web geliştirmeye daldığınızda, CSS ve HTML formlarında ustalaşmak bisikle Özel sayfa kenar boşlukları ve dinamik içerik dahil olmak üzere gelişmiş CSS tekniklerini uygulamak için Aspose.HTML for Java'yı nasıl kullanacağınızı öğrenin. Geliştiriciler için ayrıntılı, uygulamalı bir eğitim. ### [Aspose.HTML for Java ile HTML Form Düzenleme ve Gönderimi](./html-form-editing/) Bu kapsamlı adım adım kılavuzda, Aspose.HTML for Java'yı kullanarak HTML formlarını programlı olarak nasıl düzenleyeceğinizi ve göndereceğinizi öğrenin. +### [Java’da Stil Almak – HTML Yükleme ve Sorgu Seçicisi](./how-to-get-style-in-java-load-html-query-selector/) +Aspose.HTML for Java kullanarak HTML'den stil bilgilerini yükleyip sorgu seçicileriyle nasıl alacağınızı öğrenin. + {{< /blocks/products/pf/tutorial-page-section >}} {{< /blocks/products/pf/main-container >}} {{< /blocks/products/pf/main-wrap-class >}} -{{< blocks/products/products-backtop-button >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/turkish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md b/html/turkish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md new file mode 100644 index 000000000..e17722b20 --- /dev/null +++ b/html/turkish/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/_index.md @@ -0,0 +1,186 @@ +--- +category: general +date: 2026-01-14 +description: Java'da stil nasıl alınır – HTML belgesini nasıl yükleyeceğinizi, bir + sorgu seçici örneği kullanmayı ve Aspose.HTML ile background-color özelliğini okumayı + öğrenin. +draft: false +keywords: +- how to get style +- load html document +- query selector example +- background-color property +- parse html java +language: tr +og_description: Java'da stil nasıl alınır – HTML belgesi yükleme, bir query selector + örneği çalıştırma ve background‑color özelliğini alma adım adım rehberi. +og_title: Java'da stil nasıl alınır – HTML yükle ve sorgu seçicisi +tags: +- Java +- Aspose.HTML +- CSS +- DOM +title: Java'da stil nasıl alınır – HTML yükle ve sorgu seçicisi +url: /tr/java/css-html-form-editing/how-to-get-style-in-java-load-html-query-selector/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# Java’da stil nasıl alınır – HTML yükleme ve sorgu seçici + +HTML’i Java ile ayrıştırırken bir elemanın **stili nasıl alınır** diye hiç merak ettiniz mi? Belki bir scraper, bir test aracı geliştiriyorsunuz ya da oluşturulan bir sayfada görsel ipuçlarını doğrulamanız gerekiyor. İyi haber, Aspose.HTML bu işi çocuk oyuncağı haline getiriyor. Bu öğreticide bir HTML belgesi yüklemeyi, bir **sorgu seçici örneği** kullanmayı ve son olarak bir `
` elemanının **background-color özelliğini** okumayı adım adım göstereceğiz. Hiçbir sihir yok, sadece kopyalayıp yapıştırıp çalıştırabileceğiniz net Java kodları. + +## Gereksinimler + +İlerlemeye başlamadan önce şunların kurulu olduğundan emin olun: + +* **Java 17** (veya daha yeni bir JDK) – API Java 8+ ile çalışır, ancak yeni sürümler daha iyi performans sağlar. +* **Aspose.HTML for Java** kütüphanesi – Maven Central’dan (`com.aspose:aspose-html:23.10` bu yazının yazıldığı tarih itibarıyla) temin edebilirsiniz. +* En az bir `
` içinde CSS `background-color` tanımlı olan küçük bir HTML dosyası (`input.html`). Bu tanım satır içi ya da harici bir stil sayfası üzerinden olabilir. + +Hepsi bu. Ek bir framework, ağır bir tarayıcı vb. gerekmez; sadece saf Java ve Aspose.HTML yeterli. + +## Adım 1: HTML Belgesini Yükleyin + +İlk yapmanız gereken **html belgesini** belleğe **yüklemek**. Aspose.HTML’in `HTMLDocument` sınıfı dosya sistemi işlemlerini soyutlar ve sorgulayabileceğiniz bir DOM sunar. + +```java +import com.aspose.html.HTMLDocument; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); +``` + +> **Neden önemli:** Belgeyi yüklemek, ayrıştırılmış bir DOM ağacı oluşturur; bu da sonraki tüm CSS veya JavaScript değerlendirmelerinin temelidir. Dosya bulunamazsa Aspose açıklayıcı bir `FileNotFoundException` fırlatır, bu yüzden yolu iki kez kontrol edin. + +### Pro ipucu +HTML’i bir dosyadan değil bir URL’den alıyorsanız, sadece URL stringini yapıcıya geçirin – Aspose HTTP isteğini sizin yerinize halleder. + +## Adım 2: Bir Sorgu Seçici Örneği Kullanın + +Belge bellekte olduğuna göre, **sorgu seçici örneği** ile ilk `
` elemanını yakalayalım. `querySelector` metodu, tarayıcıda zaten bildiğiniz CSS seçici sözdizimini yansıtır. + +```java +import com.aspose.html.dom.Element; + +// Step 2: Select the first
element in the document +Element divElement = (Element) htmlDoc.querySelector("div"); +``` + +> **Neden önemli:** `querySelector` eşleşen ilk düğümü döndürür; tek bir elemanın stiline ihtiyacınız olduğunda mükemmeldir. Birden fazla eleman gerekiyorsa, `querySelectorAll` bir `NodeList` döndürür. + +### Kenar durumu +Seçici hiçbir öğeyle eşleşmezse, `divElement` `null` olur. Stil okumaya çalışmadan önce her zaman bunu kontrol edin: + +```java +if (divElement == null) { + System.out.println("No
found – check your selector."); + return; +} +``` + +## Adım 3: Hesaplanmış Stili Alın + +Elemanı elde ettikten sonra, bir sonraki adım **html java** yeterince ayrıştırarak nihai CSS değerlerini hesaplamaktır. Aspose.HTML ağır işi yapar: katmanlamayı, kalıtımı ve hatta harici stil sayfalarını çözer. + +```java +import com.aspose.html.css.ComputedStyleDeclaration; + +// Step 3: Obtain the computed style for the selected element +ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); +``` + +> **Neden önemli:** Hesaplanmış stil, tarayıcının tüm CSS kurallarını işledikten sonra uygulayacağı kesin değerleri yansıtır. Ham `style` özniteliğini okumaktan daha güvenilirdir; çünkü bu öznitelik eksik olabilir. + +## Adım 4: background‑color Özelliğini Alın + +Son olarak, ilgilendiğimiz **background-color özelliğini** çekiyoruz. `getPropertyValue` metodu değeri bir string olarak döndürür (ör. `rgba(255, 0, 0, 1)`). + +```java +// Step 4: Retrieve the value of a specific CSS property (background-color) +String backgroundColor = computedStyle.getPropertyValue("background-color"); + +// Step 5: Print the computed background color to the console +System.out.println("Computed background‑color: " + backgroundColor); +``` + +> **Ne göreceksiniz:** `
`inizde `background-color: #ff5733;` tanımı varsa, ister satır içi ister stil sayfası üzerinden, konsol şu şekilde bir çıktı verir: `Computed background‑color: rgb(255, 87, 51)`. + +### Yaygın tuzak +Özellik tanımlı değilse, `getPropertyValue` boş bir string döndürür. Bu, ya varsayılan bir değere dönmeyi ya da elemanın üst öğelerinin stillerini incelemeyi işaret eder. + +## Tam Çalışan Örnek + +Hepsini bir araya getirdiğimizde, işte eksiksiz, çalıştırmaya hazır program: + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.dom.Element; +import com.aspose.html.css.ComputedStyleDeclaration; + +public class ComputedStyleTutorial { + public static void main(String[] args) throws Exception { + + // Step 1: Load the HTML document from a file + HTMLDocument htmlDoc = new HTMLDocument("YOUR_DIRECTORY/input.html"); + + // Step 2: Select the first
element in the document + Element divElement = (Element) htmlDoc.querySelector("div"); + if (divElement == null) { + System.out.println("No
found – check your selector."); + return; + } + + // Step 3: Obtain the computed style for the selected element + ComputedStyleDeclaration computedStyle = divElement.getComputedStyle(); + + // Step 4: Retrieve the value of a specific CSS property (background-color) + String backgroundColor = computedStyle.getPropertyValue("background-color"); + + // Step 5: Print the computed background color to the console + System.out.println("Computed background‑color: " + backgroundColor); + } +} +``` + +**Beklenen çıktı (örnek):** + +``` +Computed background‑color: rgb(255, 87, 51) +``` + +Eğer `
`in arka plan rengi tanımlı değilse, çıktı boş bir satır olur – bu, kalıtılan stillere bakmanız gerektiğinin sinyalidir. + +## İpuçları, Püf Noktaları ve Dikkat Edilmesi Gerekenler + +| Durum | Ne Yapmalı | +|-----------|------------| +| **Birden fazla `
` elemanı** | `querySelectorAll("div")` kullanın ve `NodeList` üzerinde döngü kurun. | +| **Harici CSS dosyaları** | HTML dosyasının doğru yollarla referans verdiğinden emin olun; Aspose.HTML otomatik olarak çeker. | +| **Yalnızca satır içi `style` özniteliği** | `getComputedStyle` hâlâ çalışır – satır içi stilleri varsayılanlarla birleştirir. | +| **Performans kaygıları** | Belgeyi bir kez yükleyin, birden çok öğe sorgulamanız gerektiğinde aynı `HTMLDocument` nesnesini yeniden kullanın. | +| **Android üzerinde çalıştırma** | Aspose.HTML for Java Android’i destekler, ancak Android‑özel AAR dosyasını eklemeniz gerekir. | + +## Keşfedebileceğiniz İlgili Konular + +* **Jsoup vs. Aspose.HTML ile HTML Ayrıştırma** – hangisini ne zaman tercih etmelisiniz. +* **Hesaplanmış stilleri JSON’a aktarma** – API‑tabanlı ön‑uçlar için faydalı. +* **Ekran görüntüsü otomasyonu** – hesaplanmış stilleri Aspose.PDF ile birleştirerek görsel regresyon testleri yapın. + +--- + +### Sonuç + +Artık Aspose.HTML ile **html belgesini yükleyip**, bir **sorgu seçici örneği** çalıştırarak **background-color özelliğini** nasıl alacağınızı biliyorsunuz. Kod kendi içinde bağımsız, herhangi bir yeni JDK’da çalışır ve eksik öğeler ya da tanımsız stiller durumunu zarifçe ele alır. Bundan sonra bu yaklaşımı font boyutları, margin değerleri ya da JavaScript çalıştırıldıktan sonraki hesaplanmış değerleri çekmek için genişletebilirsiniz (Aspose.HTML script değerlendirmeyi de destekler). + +Deneyin, seçiciyi değiştirin ve başka hangi CSS hazinelerini ortaya çıkarabileceğinizi görün. Kodlamanın tadını çıkarın! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file diff --git a/html/vietnamese/java/conversion-html-to-various-image-formats/_index.md b/html/vietnamese/java/conversion-html-to-various-image-formats/_index.md index 0df69805e..bdca6f0ae 100644 --- a/html/vietnamese/java/conversion-html-to-various-image-formats/_index.md +++ b/html/vietnamese/java/conversion-html-to-various-image-formats/_index.md @@ -92,6 +92,8 @@ Học cách convert HTML to JPEG với Aspose.HTML for Java. Hướng dẫn từ Tìm hiểu cách convert HTML to PNG trong Java với Aspose.HTML. Một hướng dẫn toàn diện với các bước chi tiết. ### [Converting HTML to TIFF](./convert-html-to-tiff/) Tìm hiểu cách dễ dàng convert HTML to TIFF bằng Aspose.HTML for Java. Hướng dẫn từng bước cho việc xử lý tài liệu hiệu quả. +### [Cách đặt DPI – Render HTML sang PNG với AsposeHTML](./how-to-set-dpi-render-html-to-png-with-asposehtml/) +Hướng dẫn cách thiết lập DPI khi chuyển đổi HTML sang PNG bằng Aspose.HTML for Java. ## Câu hỏi thường gặp diff --git a/html/vietnamese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md b/html/vietnamese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md new file mode 100644 index 000000000..781d69eb9 --- /dev/null +++ b/html/vietnamese/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/_index.md @@ -0,0 +1,225 @@ +--- +category: general +date: 2026-01-14 +description: cách đặt dpi khi chuyển đổi URL sang PNG. Tìm hiểu cách render HTML thành + PNG, đặt kích thước viewport và lưu HTML dưới dạng PNG bằng Aspose.HTML trong Java. +draft: false +keywords: +- how to set dpi +- render html to png +- convert url to png +- set viewport size +- save html as png +language: vi +og_description: cách thiết lập dpi khi chuyển đổi URL sang PNG. Hướng dẫn từng bước + để render HTML thành PNG, kiểm soát kích thước viewport và lưu HTML dưới dạng PNG + bằng Aspose.HTML. +og_title: Cách đặt DPI – Render HTML sang PNG với AsposeHTML +tags: +- AsposeHTML +- Java +- image rendering +title: cách thiết lập dpi – Render HTML sang PNG với AsposeHTML +url: /vi/java/conversion-html-to-various-image-formats/how-to-set-dpi-render-html-to-png-with-asposehtml/ +--- + +{{< blocks/products/pf/main-wrap-class >}} +{{< blocks/products/pf/main-container >}} +{{< blocks/products/pf/tutorial-page-section >}} + +# cách thiết lập dpi – Render HTML thành PNG với AsposeHTML + +Bạn đã bao giờ tự hỏi **cách thiết lập dpi** cho một hình ảnh kiểu screenshot được tạo ra từ một trang web chưa? Có thể bạn cần một PNG 300 DPI cho việc in ấn, hoặc một thumbnail độ phân giải thấp cho ứng dụng di động. Trong cả hai trường hợp, bí quyết là chỉ định DPI logic bạn muốn cho engine render, sau đó để nó thực hiện phần còn lại. + +Trong tutorial này, chúng ta sẽ lấy một URL trực tiếp, render nó thành file PNG, **đặt kích thước viewport**, điều chỉnh DPI, và cuối cùng **lưu HTML dưới dạng PNG**—tất cả bằng Aspose.HTML cho Java. Không cần trình duyệt bên ngoài, không cần công cụ dòng lệnh rắc rối—chỉ cần đoạn mã Java sạch bạn có thể đưa vào bất kỳ dự án Maven hoặc Gradle nào. + +> **Mẹo chuyên nghiệp:** Nếu bạn chỉ cần một thumbnail nhanh, bạn có thể giữ DPI ở 96 DPI (mặc định cho hầu hết màn hình). Đối với tài sản sẵn sàng in, hãy tăng lên 300 DPI hoặc cao hơn. + +![ví dụ cách thiết lập dpi](https://example.com/images/how-to-set-dpi.png "ví dụ cách thiết lập dpi") + +## Những gì bạn cần + +- **Java 17** (hoặc bất kỳ JDK hiện đại nào). +- **Aspose.HTML for Java** 24.10 trở lên. Bạn có thể tải từ Maven Central: + +```xml + + com.aspose + aspose-html + 24.10 + +``` + +- Kết nối internet để tải trang mục tiêu (ví dụ sử dụng `https://example.com/sample.html`). +- Quyền ghi vào thư mục đầu ra. + +Đó là tất cả—không cần Selenium, không cần Chrome headless. Aspose.HTML thực hiện render trong‑process, nghĩa là bạn ở trong JVM và tránh chi phí khởi chạy trình duyệt. + +## Bước 1 – Tải tài liệu HTML từ URL + +Đầu tiên chúng ta tạo một thể hiện `HTMLDocument` trỏ tới trang muốn chụp. Constructor sẽ tự động tải HTML, phân tích và chuẩn bị DOM. + +```java +import com.aspose.html.HTMLDocument; +import java.nio.file.Paths; + +// Load the remote page +HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); +``` + +*Lý do quan trọng:* Bằng cách tải tài liệu trực tiếp, bạn bỏ qua việc phải dùng một HTTP client riêng. Aspose.HTML hỗ trợ chuyển hướng, cookie, và thậm chí xác thực cơ bản nếu bạn nhúng thông tin đăng nhập trong URL. + +## Bước 2 – Xây dựng Sandbox với DPI và Viewport mong muốn + +Một **sandbox** là cách Aspose.HTML mô phỏng môi trường trình duyệt. Ở đây chúng ta chỉ định nó giả vờ là màn hình 1280 × 720 và, quan trọng nhất, đặt **device DPI**. Thay đổi DPI sẽ thay đổi mật độ pixel của hình ảnh render mà không ảnh hưởng tới kích thước logic. + +```java +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; + +// Create a sandbox that simulates a 1280×720 screen at 96 DPI +SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width, height in pixels + .setDeviceDpi(96) // logical DPI (change to 300 for print) + .setUserAgent("AsposeHTML/24.10") // optional custom user‑agent + .build(); + +// Apply the sandbox to the document +htmlDoc.setSandbox(sandbox); +``` + +*Lý do bạn có thể điều chỉnh các giá trị này:* +- **Kích thước viewport** kiểm soát cách các media query CSS (`@media (max-width: …)`) hoạt động. +- **Device DPI** ảnh hưởng đến kích thước thực tế của hình ảnh khi in. Hình ảnh 96 DPI trông ổn trên màn hình; hình ảnh 300 DPI giữ độ nét trên giấy. + +Nếu bạn cần một thumbnail vuông, chỉ cần thay đổi `setViewportSize(500, 500)` và giữ DPI thấp. + +## Bước 3 – Chọn PNG làm định dạng đầu ra + +Aspose.HTML hỗ trợ một số định dạng raster (PNG, JPEG, BMP, GIF). PNG không mất dữ liệu, rất phù hợp cho screenshot nơi bạn muốn mọi pixel được bảo toàn. + +```java +import com.aspose.html.rendering.ImageSaveOptions; + +// Prepare PNG save options +ImageSaveOptions pngOptions = new ImageSaveOptions(); +pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); +``` + +Bạn cũng có thể điều chỉnh mức nén (`pngOptions.setCompressionLevel(9)`) nếu lo lắng về kích thước file. + +## Bước 4 – Render và Lưu hình ảnh + +Bây giờ chúng ta yêu cầu tài liệu **lưu** chính nó dưới dạng hình ảnh. Phương thức `save` nhận đường dẫn file và các tùy chọn đã cấu hình trước. + +```java +// Define the output path (replace with your own directory) +String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + +// Render the document to a PNG file +htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + +System.out.println("Rendering completed."); +``` + +Khi chương trình kết thúc, bạn sẽ thấy file PNG tại `YOUR_DIRECTORY/sandboxed.png`. Mở nó—nếu bạn đã đặt DPI là 300, metadata của ảnh sẽ phản ánh giá trị đó, mặc dù kích thước pixel vẫn là 1280 × 720. + +## Bước 5 – Xác minh DPI (Tùy chọn nhưng hữu ích) + +Nếu bạn muốn kiểm tra lại DPI đã thực sự được áp dụng, có thể đọc metadata PNG bằng thư viện nhẹ như **metadata‑extractor**: + +```java +import com.drew.imaging.ImageMetadataReader; +import com.drew.metadata.png.PngDirectory; + +File pngFile = new File(outputPath); +var metadata = ImageMetadataReader.readMetadata(pngFile); +var pngDir = metadata.getFirstDirectoryOfType(PngDirectory.class); +int dpi = pngDir.getInt(PngDirectory.TAG_PIXELS_PER_UNIT_X); +System.out.println("DPI stored in PNG: " + dpi); +``` + +Bạn sẽ thấy `300` (hoặc giá trị bạn đã đặt) được in ra console. Bước này không bắt buộc để render, nhưng là một cách kiểm tra nhanh, đặc biệt khi bạn tạo tài sản cho quy trình in ấn. + +## Các câu hỏi thường gặp & Trường hợp đặc biệt + +### “Nếu trang sử dụng JavaScript để tải nội dung thì sao?” + +Aspose.HTML thực thi một **tập con giới hạn** của JavaScript. Đối với hầu hết các trang tĩnh, nó hoạt động ngay lập tức. Nếu trang phụ thuộc mạnh vào các framework phía client (React, Angular, Vue), bạn có thể cần pre‑render trang hoặc dùng trình duyệt headless thay thế. Tuy nhiên, việc thiết lập DPI vẫn diễn ra tương tự một khi DOM đã sẵn sàng. + +### “Tôi có thể render PDF thay vì PNG không?” + +Chắc chắn rồi. Thay `ImageSaveOptions` bằng `PdfSaveOptions` và đổi phần mở rộng đầu ra thành `.pdf`. Cài đặt DPI vẫn ảnh hưởng tới cách các hình ảnh nhúng được raster hoá. + +### “Cách chụp màn hình độ phân giải cao cho màn hình retina?” + +Chỉ cần gấp đôi kích thước viewport trong khi giữ DPI ở 96 DPI, hoặc giữ viewport và tăng DPI lên 192. PNG quả sẽ chứa gấp đôi số pixel, mang lại cảm giác retina sắc nét. + +### “Có cần dọn dẹp tài nguyên không?” + +`HTMLDocument` triển khai `AutoCloseable`. Trong ứng dụng thực tế, hãy bọc nó trong khối try‑with‑resources: + +```java +try (HTMLDocument doc = new HTMLDocument(url)) { + // configure sandbox, render, etc. +} +``` + +Điều này sẽ giải phóng các tài nguyên native kịp thời. + +## Ví dụ hoàn chỉnh (Sẵn sàng sao chép) + +Dưới đây là chương trình đầy đủ, sẵn sàng chạy. Thay `YOUR_DIRECTORY` bằng thư mục thực tế trên máy của bạn. + +```java +import com.aspose.html.HTMLDocument; +import com.aspose.html.rendering.ImageSaveOptions; +import com.aspose.html.rendering.SandboxConfiguration; +import com.aspose.html.rendering.SandboxConfigurationBuilder; +import java.nio.file.Paths; + +public class RenderHtmlToPng { + public static void main(String[] args) { + // 1️⃣ Load the HTML document from a URL + HTMLDocument htmlDoc = new HTMLDocument("https://example.com/sample.html"); + + // 2️⃣ Create a sandbox – set viewport size and DPI + SandboxConfiguration sandbox = new SandboxConfigurationBuilder() + .setViewportSize(1280, 720) // width × height in pixels + .setDeviceDpi(96) // change to 300 for print‑ready PNG + .setUserAgent("AsposeHTML/24.10") + .build(); + + htmlDoc.setSandbox(sandbox); // apply sandbox to the document + + // 3️⃣ Prepare PNG save options + ImageSaveOptions pngOptions = new ImageSaveOptions(); + pngOptions.setFormat(ImageSaveOptions.ImageFormat.Png); + + // 4️⃣ Render and save + String outputPath = "YOUR_DIRECTORY/sandboxed.png"; + htmlDoc.save(Paths.get(outputPath).toString(), pngOptions); + + System.out.println("Rendering completed. Check: " + outputPath); + } +} +``` + +Chạy lớp, và bạn sẽ nhận được một PNG tuân thủ **cách thiết lập dpi** mà bạn đã chỉ định. + +## Kết luận + +Chúng ta đã đi qua **cách thiết lập dpi** khi **render HTML thành PNG**, đề cập đến bước **đặt kích thước viewport**, và chỉ ra cách **lưu HTML dưới dạng PNG** bằng Aspose.HTML cho Java. Những điểm chính cần nhớ là: + +- Sử dụng **sandbox** để kiểm soát DPI và viewport. +- Chọn **ImageSaveOptions** phù hợp cho đầu ra không mất dữ liệu. +- Kiểm tra metadata DPI nếu cần đảm bảo chất lượng in. + +Từ đây bạn có thể thử nghiệm với các giá trị DPI khác nhau, viewport lớn hơn, hoặc thậm chí xử lý hàng loạt danh sách URL. Muốn chuyển đổi toàn bộ website thành các thumbnail PNG? Chỉ cần lặp qua mảng URL và tái sử dụng cùng một cấu hình sandbox. + +Chúc bạn render thành công, và hy vọng các screenshot luôn đạt độ pixel‑perfect! + +{{< /blocks/products/pf/tutorial-page-section >}} +{{< /blocks/products/pf/main-container >}} +{{< /blocks/products/pf/main-wrap-class >}} +{{< blocks/products/products-backtop-button >}} \ No newline at end of file