Changed initial culture detection

src/Components/Web.JS/src/GlobalExports.ts

@@ -74,6 +74,7 @@ export interface IBlazor {
     renderBatch?: (browserRendererId: number, batchAddress: Pointer) => void;
     getConfig?: (fileName: string) => Uint8Array | undefined;
     getApplicationEnvironment?: () => string;
+    getApplicationCulture?: () => string;
     dotNetCriticalError?: any;
     loadLazyAssembly?: any;
     loadSatelliteAssemblies?: any;

src/Components/Web.JS/src/Platform/Mono/MonoPlatform.ts

@@ -154,6 +154,7 @@ function prepareRuntimeConfig(options: Partial<WebAssemblyStartOptions>, onConfi
     }
 
     Blazor._internal.getApplicationEnvironment = () => loadedConfig.applicationEnvironment!;
+    Blazor._internal.getApplicationCulture = () => loadedConfig.applicationCulture!;
 
     onConfigLoadedCallback?.(loadedConfig);
 

src/Components/WebAssembly/WebAssembly/src/Hosting/WebAssemblyCultureProvider.cs

@@ -32,7 +32,7 @@ internal WebAssemblyCultureProvider(CultureInfo initialCulture, CultureInfo init
     internal static void Initialize()
     {
         Instance = new WebAssemblyCultureProvider(
-            initialCulture: CultureInfo.CurrentCulture,
+            initialCulture: CultureInfo.GetCultureInfo(WebAssemblyCultureProviderInterop.GetApplicationCulture() ?? CultureInfo.InvariantCulture.Name),
             initialUICulture: CultureInfo.CurrentUICulture);
     }
 
@@ -48,8 +48,7 @@ public void ThrowIfCultureChangeIsUnsupported()
         // The current method is invoked as part of WebAssemblyHost.RunAsync i.e. after user code in Program.MainAsync has run
         // thus allows us to detect if the culture was changed by user code.
         if (Environment.GetEnvironmentVariable("__BLAZOR_SHARDED_ICU") == "1" &&
-            ((!CultureInfo.CurrentCulture.Name.Equals(InitialCulture.Name, StringComparison.Ordinal) ||
-              !CultureInfo.CurrentUICulture.Name.Equals(InitialUICulture.Name, StringComparison.Ordinal))))
+            (!CultureInfo.CurrentCulture.Name.Equals(InitialCulture.Name, StringComparison.Ordinal)))
         {
             throw new InvalidOperationException("Blazor detected a change in the application's culture that is not supported with the current project configuration. " +
                 "To change culture dynamically during startup, set <BlazorWebAssemblyLoadAllGlobalizationData>true</BlazorWebAssemblyLoadAllGlobalizationData> in the application's project file.");
@@ -118,5 +117,8 @@ private partial class WebAssemblyCultureProviderInterop
     {
         [JSImport("INTERNAL.loadSatelliteAssemblies")]
         public static partial Task LoadSatelliteAssemblies(string[] culturesToLoad);
+
+        [JSImport("Blazor._internal.getApplicationCulture", "blazor-internal")]
+        public static partial string GetApplicationCulture();
     }
 }

src/Components/WebAssembly/WebAssembly/src/Services/IInternalJSImportMethods.cs

@@ -8,6 +8,8 @@ internal interface IInternalJSImportMethods
     string GetPersistedState();
 
     string GetApplicationEnvironment();
+
+    string GetApplicationCulture();
 
     void AttachRootComponentToElement(string domElementSelector, int componentId, int rendererId);
 

src/Components/WebAssembly/WebAssembly/src/Services/InternalJSImportMethods.cs

@@ -27,6 +27,9 @@ public static async Task<RootComponentOperationBatch> GetInitialComponentUpdate(
     public string GetApplicationEnvironment()
         => GetApplicationEnvironmentCore();
 
+    public string GetApplicationCulture()
+        => GetApplicationCultureCore();
+
     public void AttachRootComponentToElement(string domElementSelector, int componentId, int rendererId)
         => AttachRootComponentToElementCore(domElementSelector, componentId, rendererId);
 
@@ -72,6 +75,9 @@ public string RegisteredComponents_GetParameterValues(int id)
     [JSImport("Blazor._internal.getApplicationEnvironment", "blazor-internal")]
     private static partial string GetApplicationEnvironmentCore();
 
+    [JSImport("Blazor._internal.getApplicationCulture", "blazor-internal")]
+    private static partial string GetApplicationCultureCore();
+
     [JSImport("Blazor._internal.attachRootComponentToElement", "blazor-internal")]
     private static partial void AttachRootComponentToElementCore(string domElementSelector, int componentId, int rendererId);
 

src/Components/WebAssembly/WebAssembly/test/TestInternalJSImportMethods.cs

@@ -16,6 +16,9 @@ public TestInternalJSImportMethods(string environment = "Production")
 
     public string GetApplicationEnvironment()
         => _environment;
+
+    public string GetApplicationCulture()
+        => "en-US";
 
     public string GetPersistedState()
         => null;