Added new kb article generate-pdf-with-headers-footers-from-separate-html-files (#663)

* Added new kb article generate-pdf-with-headers-footers-from-separate-html-files

* add images

* polished html code snippets

---------

Co-authored-by: KB Bot <[email protected]>
Co-authored-by: Desislava Yordanova <[email protected]>

Author: 3 people

knowledge-base/generate-pdf-with-headers-footers-from-separate-html-files.md

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+---
+title: Generating PDF with Headers and Footers from Separate HTML Files
+description: Learn how to generate PDF documents with headers and footers using separate HTML files.
+type: how-to
+page_title: Generating PDF with Headers and Footers from Separate HTML Files
+meta_title: Generating PDF with Headers and Footers from Separate HTML Files
+slug: generate-pdf-with-headers-footers-from-separate-html-files
+tags: telerik, document, processing, word, header, footer, pdf, html, merge
+res_type: kb
+ticketid: 1702165
+---
+
+## Environment
+
+| Version | Product | Author | 
+| ---- | ---- | ---- | 
+| 2025.3.806| RadWordsProcessing |[Desislava Yordanova](https://www.telerik.com/blogs/author/desislava-yordanova)| 
+
+## Description
+
+Learn how to combine **separate** HTML files for **header**, **footer** and **content** into one common document and product a PDF document with the result.
+
+## Solution
+
+To generate a PDF with separate headers and footers, process the HTML files using RadWordsProcessing. Follow these steps:
+
+1. **Import the HTML content**: Use the [HtmlFormatProvider]({%slug radwordsprocessing-overview%}) to import the HTML content into [RadFlowDocument]({%slug radwordsprocessing-model-radflowdocument%}) objects.
+2. **Add headers and footers**: Use the [DocumentElementImporter]({%slug radwordsprocessing-editing-import-document-element%}) to insert [header and footer]({%slug radwordsprocessing-model-headers-footers%}) content into the main document.
+3. **Export the document to PDF**: Use the [PdfFormatProvider]({%slug radwordsprocessing-formats-and-conversion-pdf-pdfformatprovider%}) to export the final document to PDF format.
+
+### Code Example
+
+```csharp
+        static void Main(string[] args)
+        {
+
+            string headerHtml = "\r\n<p style=\"text-align: center; font-size: 16pt; font-weight: bold;\">\r\n    Company Name\r\n</p>\r\n<p style=\"text-align: center; font-size: 12pt;\">\r\n    Document Title\r\n</p>\r\n<p style=\"text-align: center; font-size: 10pt;\">\r\n    Date: October 28, 2025\r\n</p>\r\n";
+            string contentHtml = "<p>This is the main content of the document.</p>";
+            string footerHtml = "\r\n<p style=\"text-align: center; font-size: 10pt;\">\r\n    Confidential - For Internal Use Only\r\n</p>\r\n<p style=\"text-align: center; font-size: 10pt;\">\r\n    Page 1 of 1\r\n</p>\r\n";
+
+            var htmlProvider = new HtmlFormatProvider();
+
+            // Load each HTML file into a separate document
+            RadFlowDocument headerDoc = htmlProvider.Import(headerHtml, TimeSpan.FromSeconds(10));
+            RadFlowDocument contentDoc = htmlProvider.Import(contentHtml, TimeSpan.FromSeconds(10));
+            RadFlowDocument footerDoc = htmlProvider.Import(footerHtml, TimeSpan.FromSeconds(10));
+
+            // Create importer for header
+            var headerImporter = new DocumentElementImporter(contentDoc, headerDoc, ConflictingStylesResolutionMode.UseTargetStyle);
+            Header defaultHeader = contentDoc.Sections.First().Headers.Add();
+
+            foreach (var block in headerDoc.Sections.First().Blocks)
+            {
+                BlockBase importedBlock = headerImporter.Import(block);
+                defaultHeader.Blocks.Add(importedBlock);
+            }
+
+            // Create importer for footer
+            var footerImporter = new DocumentElementImporter(contentDoc, footerDoc, ConflictingStylesResolutionMode.UseTargetStyle);
+            Footer defaultFooter = contentDoc.Sections.First().Footers.Add();
+
+            foreach (var block in footerDoc.Sections.First().Blocks)
+            {
+                BlockBase importedBlock = footerImporter.Import(block);
+                defaultFooter.Blocks.Add(importedBlock);
+            }
+
+            // Export to PDF
+            var pdfProvider = new PdfFormatProvider();
+            string outputFilePath = "FinalDocument.pdf";
+            using (var outputStream = File.Create(outputFilePath))
+            {
+                pdfProvider.Export(contentDoc, outputStream, TimeSpan.FromSeconds(10));
+            }
+            Process.Start(new ProcessStartInfo() { FileName = outputFilePath, UseShellExecute = true });
+        }
+```
+Let's have the following 3 separate HTML files: 
+
+* Header HTML:
+
+```html
+<p style="text-align: center; font-size: 16pt; font-weight: bold;">
+    Company Name
+</p>
+<p style="text-align: center; font-size: 12pt;">
+    Document Title
+</p>
+<p style="text-align: center; font-size: 10pt;">
+    Date: October 28, 2025
+</p>
+
+``` 
+![HTML Header](images/html-header-preview.png)
+
+* Footer HTML
+
+```html
+<p style="text-align: center; font-size: 10pt;">
+    Confidential - For Internal Use Only
+</p>
+<p style="text-align: center; font-size: 10pt;">
+    Page 1 of 1
+</p>
+
+``` 
+![HTML Footer](images/html-footer-preview.png)    
+
+* Content HTML
+
+```html
+<p>This is the main content of the document.</p>
+
+``` 
+![HTML Content](images/html-content-preview.png)
+
+The result PDF document combined all of the HTML files in one common document:
+
+![Combined PDF](images/combined_pdf.png)  
+
+## See Also
+
+- [DocumentElementImporter]({%slug radwordsprocessing-editing-import-document-element%}) 
+- [Headers and footers]({%slug radwordsprocessing-model-headers-footers%})