Add demo exception handling to HybridWebView sample

Copilot · mattleibow · mattleibow · commit 4014e400c5ca · 2025-09-09T03:38:28.000+02:00
- Added ThrowException and ThrowExceptionAsync methods to demonstrate new functionality
- Added JavaScript functions to test and showcase exception catching
- Added UI buttons to trigger exception handling tests
- Updated sample to show both error and success scenarios

Co-authored-by: mattleibow &lt;1096616+mattleibow@users.noreply.github.com&gt;
diff --git a/src/Controls/samples/Controls.Sample/Pages/Controls/HybridWebViewPage.xaml.cs b/src/Controls/samples/Controls.Sample/Pages/Controls/HybridWebViewPage.xaml.cs
@@ -153,6 +153,21 @@ public async Task<SyncReturn> DoAsyncWorkParamsReturn(int i, string s)
 					Value = i,
 				};
 			}
+
+			// Demo method that throws an exception to showcase error handling
+			public void ThrowException()
+			{
+				Debug.WriteLine("ThrowException called - about to throw");
+				throw new InvalidOperationException("This is a test exception thrown from C# code!");
+			}
+
+			// Demo async method that throws an exception
+			public async Task<string> ThrowExceptionAsync()
+			{
+				Debug.WriteLine("ThrowExceptionAsync called - about to throw");
+				await Task.Delay(100);
+				throw new ArgumentException("This is an async test exception thrown from C# code!");
+			}
 		}
 
 		public class SyncReturn
diff --git a/src/Controls/samples/Controls.Sample/Resources/Raw/HybridSamplePage/index.html b/src/Controls/samples/Controls.Sample/Resources/Raw/HybridSamplePage/index.html
@@ -93,6 +93,32 @@
             LogMessage("Invoked DoAsyncWorkParamsReturn, return value: message=" + retValue.Message + ", value=" + retValue.Value);
         }
 
+        // Demo functions to test exception handling
+        async function InvokeThrowException() {
+            LogMessage("Invoking ThrowException");
+            try {
+                await window.HybridWebView.InvokeDotNet('ThrowException');
+                LogMessage("ThrowException unexpectedly succeeded!");
+            } catch (ex) {
+                LogMessage("Caught exception from ThrowException: " + ex.message);
+                LogMessage("Exception type: " + (ex.dotNetErrorType || "Unknown"));
+                if (ex.dotNetStackTrace) {
+                    LogMessage("Stack trace: " + ex.dotNetStackTrace.substring(0, 200) + "...");
+                }
+            }
+        }
+
+        async function InvokeThrowExceptionAsync() {
+            LogMessage("Invoking ThrowExceptionAsync");
+            try {
+                const result = await window.HybridWebView.InvokeDotNet('ThrowExceptionAsync');
+                LogMessage("ThrowExceptionAsync unexpectedly succeeded with result: " + result);
+            } catch (ex) {
+                LogMessage("Caught async exception from ThrowExceptionAsync: " + ex.message);
+                LogMessage("Exception type: " + (ex.dotNetErrorType || "Unknown"));
+            }
+        }
+
     </script>
 </head>
 <body>
@@ -114,6 +140,11 @@
         <button onclick="InvokeDoAsyncWorkReturn()">Call C# async method (no params) and get simple return value</button>
         <button onclick="InvokeDoAsyncWorkParamsReturn()">Call C# async method (params) and get complex return value</button>
     </div>
+    <div>
+        <strong>Exception Handling Tests:</strong>
+        <button onclick="InvokeThrowException()">Test C# Exception Handling</button>
+        <button onclick="InvokeThrowExceptionAsync()">Test C# Async Exception Handling</button>
+    </div>
     <div>
         Log: <textarea readonly id="messageLog" style="width: 80%; height: 10em;"></textarea>
     </div>
