dotnet · guardrex · Apr 14, 2022 · Apr 14, 2022 · Apr 14, 2022 · Apr 14, 2022
@@ -5,7 +5,7 @@ description: Learn how to manage request routing and navigation in Blazor Hybrid
 monikerRange: '>= aspnetcore-6.0'
 ms.author: riande
 ms.custom: "mvc"
-ms.date: 02/24/2022
+ms.date: 04/14/2022
 no-loc: [".NET MAUI", "Mac Catalyst", "Blazor Hybrid", Home, Privacy, Kestrel, appsettings.json, "ASP.NET Core Identity", cookie, Cookie, Blazor, "Blazor Server", "Blazor WebAssembly", "Identity", "Let's Encrypt", Razor, SignalR]
 uid: blazor/hybrid/routing
 ---
@@ -15,10 +15,27 @@ This article explains how to manage request routing and navigation in Blazor Hyb
 
 [!INCLUDE[](~/blazor/includes/blazor-hybrid-preview-notice.md)]
 
-Register to the `ExternalNavigationStarting` event and set the `ExternalLinkNavigationEventArgs.ExternalLinkNavigationPolicy` property to change link handling behavior. The `ExternalLinkNavigationPolicy` enumeration (`enum`) allows setting link handling behavior to `OpenInExternalBrowser`, `InsecureOpenInWebView`, and `CancelNavigation`. The `ExternalLinkNavigationEventArgs.Uri` property can be used to dynamically set link handling behavior.
+[!INCLUDE[](~/blazor/includes/net-maui-release-candidate-notice.md)]
+
+Default URI request routing behavior:
+
+* A link is *internal* if the host name and scheme match between the app's origin URI and the request URI. When the host names and schemes don't match or if the link sets `target="_blank"`, the link is considered *external*.
+* If the link is internal, the link is opened in the `BlazorWebView` by the app.
+* If the link is external, the link is opened by an app determined by the device based on the device's registered handler for the link's scheme.
+* For internal links that appear to request a file because the last segment of the URI uses dot notation (for example, `/file.x`, `/Maryia.Melnyk`, `/image.gif`) but don't point to any static content:
+  * WPF and Windows Forms: The host page content is returned.
+  * .NET MAUI: A 404 response is returned.
+
+To change the link handling behavior for links that don't set `target="_blank"`, register the `UrlLoading` event and set the `UrlLoadingEventArgs.UrlLoadingStrategy` property. The `UrlLoadingStrategy` enumeration allows setting link handling behavior to any of the following values:
+
+* `OpenExternally`: Load the URL using an app determined by the device. This is the default strategy for URIs with an external host.
+* `OpenInWebView`: Load the URL within the `BlazorWebView`. This is the default strategy for URLs with a host matching the app origin. ***Don't use this strategy for external links unless you can ensure the destination URI is fully trusted.***
+* `CancelLoad`: Cancels the current URL loading attempt.
+
+The `UrlLoadingEventArgs.Url` property is used to get or dynamically set the URL.
 
 > [!WARNING]
-> External links are opened in the device's default browser by default. Opening external links within a `BlazorWebView` can introduce security vulnerabilities and should ***not*** be enabled unless you can ensure that the external links are fully trusted.
+> By default, external links are opened in an app determined by the device. Opening external links within a `BlazorWebView` can introduce security vulnerabilities and should ***not*** be enabled unless you can ensure that the external links are fully trusted.
 
 ## Namespace
 
@@ -33,45 +50,42 @@ using Microsoft.AspNetCore.Components.WebView;
 Add the event handler to the constructor of the `Page` where the `BlazorWebView` is constructed:
 
 ```csharp
-blazorWebView.ExternalNavigationStarting += 
-    (sender, externalLinkNavigationEventArgs) =>
+blazorWebView.UrlLoading += 
+    (sender, urlLoadingEventArgs) =>
     {
-        externalLinkNavigationEventArgs.ExternalLinkNavigationPolicy = 
-            ExternalLinkNavigationPolicy.InsecureOpenInWebView;
+        urlLoadingEventArgs.UrlLoadingStrategy = UrlLoadingStrategy.OpenInWebView;
     };
 ```
 
 ## WPF
 
-Add the `ExternalNavigationStarting="Handle_ExternalNavigationStarting"` attribute to the `BlazorWebView` control in the `.xaml` file:
+Add the `UrlLoading="Handle_UrlLoading"` attribute to the `BlazorWebView` control in the `.xaml` file:
 
 ```xaml
 <blazor:BlazorWebView HostPage="wwwroot\index.html" 
     Services="{StaticResource services}" 
     x:Name="blazorWebView" 
-    ExternalNavigationStarting="Handle_ExternalNavigationStarting" >
+    UrlLoading="Handle_UrlLoading" >
 ```
 
 Add the event handler in the `.xaml.cs` file:
 
 ```csharp
-private void Handle_ExternalNavigationStarting(
-    object sender, ExternalLinkNavigationEventArgs externalLinkNavigationEventArgs)
+private void Handle_UrlLoading(object sender, 
+    UrlLoadingEventArgs urlLoadingEventArgs)
 {
-    externalLinkNavigationEventArgs.ExternalLinkNavigationPolicy = 
-        ExternalLinkNavigationPolicy.InsecureOpenInWebView;
+    urlLoadingEventArgs.UrlLoadingStrategy = UrlLoadingStrategy.OpenInWebView;
 }
 ```
 
-## Winforms
+## Windows Forms
 
 In the constructor of the form containing the `BlazorWebView` control, add the following event registration:
 
 ```csharp
-blazorWebView.ExternalNavigationStarting += 
-    (sender, externalLinkNavigationEventArgs) =>
+blazorWebView.UrlLoading += 
+    (sender, urlLoadingEventArgs) =>
     {
-        externalLinkNavigationEventArgs.ExternalLinkNavigationPolicy = 
-            ExternalLinkNavigationPolicy.InsecureOpenInWebView;
+        urlLoadingEventArgs.UrlLoadingStrategy = UrlLoadingStrategy.OpenInWebView;
     };
 ```
@@ -59,7 +59,7 @@ The Android :::no-loc text="Web View"::: is distributed and updated via the [Goo
 
 iOS and Mac Catalyst both use [`WKWebView`](https://developer.apple.com/documentation/webkit/wkwebview), a Safari-based control, which is updated by the operating system. Similar to the [Android](#android) case, determine the :::no-loc text="Web View"::: version by reading the :::no-loc text="Web View":::'s [`User-Agent`](https://developer.mozilla.org/docs/Web/HTTP/Headers/User-Agent) string.
 
-### Windows (.NET MAUI, WPF, WinForms)
+### Windows (.NET MAUI, WPF, Windows Forms)
 
 On Windows, the Chromium-based [Microsoft Edge `WebView2`](/microsoft-edge/webview2/) is required to run Blazor web apps. By default, the newest installed version of `WebView2` (known as the [Evergreen distribution](/microsoft-edge/webview2/concepts/distribution#details-about-the-fixed-version-runtime-distribution-mode)) is used.
 

@@ -18,6 +18,8 @@ This tutorial shows you how to build and run a .NET MAUI Blazor app. You learn h
 > * Run the app on Windows
 > * Run the app in the Android emulator
 
+[!INCLUDE[](~/blazor/includes/blazor-hybrid-preview-notice.md)]
+
 [!INCLUDE[](~/blazor/includes/net-maui-release-candidate-notice.md)]
 
 ## Prerequisites

@@ -2,4 +2,4 @@
 no-loc: [".NET MAUI", "Mac Catalyst", "Blazor Hybrid", Home, Privacy, Kestrel, appsettings.json, "ASP.NET Core Identity", cookie, Cookie, Blazor, "Blazor Server", "Blazor WebAssembly", "Identity", "Let's Encrypt", Razor, SignalR]
 ---
 > [!IMPORTANT]
-> .NET MAUI is a Release Candidate and may be modified before final release. As with other .NET Release Candidates, the 17.2 Preview 3 release is covered by a "go live" support policy, meaning .NET MAUI is supported by Microsoft for production apps. Microsoft makes no warranties, express or implied, with respect to the information provided in Blazor Hybrid articles.
+> .NET MAUI is a Release Candidate and may be modified before final release. As with other .NET Release Candidates, the 17.2 Preview 3 release is covered by a "go live" support policy, meaning .NET MAUI is supported by Microsoft for production apps.