Implement "copy if newer" for resources when sample app is packaged

Author: AndrewKeepCoding

WinUI3Localizer.SampleApp/App.xaml.cs

@@ -5,6 +5,7 @@
 using Serilog;
 using System;
 using System.IO;
+using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
 using Windows.Storage;
 
@@ -32,20 +33,32 @@ protected override async void OnLaunched(LaunchActivatedEventArgs args)
         this.window.Activate();
     }
 
-    private static async Task CreateStringResourceFileIfNotExists(StorageFolder stringsFolder, string language, string resourceFileName)
+    private static async Task MakeSureStringResourceFileExists(StorageFolder stringsFolder, string language, string resourceFileName)
     {
         StorageFolder languageFolder = await stringsFolder.CreateFolderAsync(
-            language,
+            desiredName: language,
             CreationCollisionOption.OpenIfExists);
 
-        if (await languageFolder.TryGetItemAsync(resourceFileName) is null)
+        string appResourceFilePath = Path.Combine(stringsFolder.Name, language, resourceFileName);
+        StorageFile appResourceFile = await LoadStringResourcesFileFromAppResource(appResourceFilePath);
+
+        IStorageItem? localResourceFile = await languageFolder.TryGetItemAsync(resourceFileName);
+
+        if (localResourceFile is null ||
+            (await GetModifiedDate(appResourceFile)) > (await GetModifiedDate(localResourceFile)))
         {
-            string resourceFilePath = Path.Combine(stringsFolder.Name, language, resourceFileName);
-            StorageFile resourceFile = await LoadStringResourcesFileFromAppResource(resourceFilePath);
-            _ = await resourceFile.CopyAsync(languageFolder);
+            _ = await appResourceFile.CopyAsync(
+                destinationFolder: languageFolder,
+                desiredNewName: appResourceFile.Name,
+                option: NameCollisionOption.ReplaceExisting);
         }
     }
 
+    private static async Task<DateTimeOffset> GetModifiedDate(IStorageItem file)
+    {
+        return (await file.GetBasicPropertiesAsync()).DateModified;
+    }
+
     private static async Task<StorageFile> LoadStringResourcesFileFromAppResource(string filePath)
     {
         Uri resourcesFileUri = new($"ms-appx:///{filePath}");
@@ -115,9 +128,9 @@ private async Task InitializeLocalizer()
 
         // Create string resources file from app resources if doesn't exists.
         string resourceFileName = "Resources.resw";
-        await CreateStringResourceFileIfNotExists(stringsFolder, "en-US", resourceFileName);
-        await CreateStringResourceFileIfNotExists(stringsFolder, "es-ES", resourceFileName);
-        await CreateStringResourceFileIfNotExists(stringsFolder, "ja", resourceFileName);
+        await MakeSureStringResourceFileExists(stringsFolder, "en-US", resourceFileName);
+        await MakeSureStringResourceFileExists(stringsFolder, "es-ES", resourceFileName);
+        await MakeSureStringResourceFileExists(stringsFolder, "ja", resourceFileName);
 #endif
 
         ILocalizer localizer = await new LocalizerBuilder()

WinUI3Localizer.SampleApp/WinUI3Localizer.SampleApp.csproj

@@ -70,7 +70,15 @@
     <DefineConstants>IS_NON_PACKAGED</DefineConstants>
   </PropertyGroup>
 
-  <!-- Copy all "Resources.resw" files in the "Strings" folder to the output folder. -->
+  <!-- If the app is "Non-Packaged", copy the "Strings" folder to the output directory -->
+  <Target Name="CopyStringResources" AfterTargets="Build">
+    <ItemGroup>
+      <StringResources Include="$(ProjectDir)Strings\**\*.*" />
+    </ItemGroup>
+    <Copy SourceFiles="@(StringResources)" DestinationFiles="$(OutDir)Strings\%(RecursiveDir)%(Filename)%(Extension)" SkipUnchangedFiles="true" />
+  </Target>
+
+  <!-- Embed all "Resources.resw" files in the "Strings" folder to the output folder. -->
   <ItemGroup>
     <Content Include="Strings\**\*.resw">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>