Add demo test methods and final documentation for HybridWebView exception handling

Copilot · mattleibow · mattleibow · commit c7c6feff532a · 2025-09-09T03:32:01.000+02:00
Co-authored-by: mattleibow &lt;1096616+mattleibow@users.noreply.github.com&gt;
diff --git a/src/Controls/tests/DeviceTests/Elements/HybridWebView/HybridWebViewTests.cs b/src/Controls/tests/DeviceTests/Elements/HybridWebView/HybridWebViewTests.cs
@@ -417,6 +417,31 @@ public Task InvokeDotNetExceptionHandling(string methodName, string expectedExce
 				Assert.Equal(methodName, invokeJavaScriptTarget.LastMethodCalled);
 			});
 
+		[Fact]
+		public Task DemonstrateExceptionHandlingFunctionality() =>
+			RunTest("exceptiondemo.html", async (hybridWebView) =>
+			{
+				var invokeJavaScriptTarget = new TestDotNetMethods();
+				hybridWebView.SetInvokeJavaScriptTarget(invokeJavaScriptTarget);
+
+				// Test successful method call
+				var successResult = await hybridWebView.EvaluateJavaScriptAsync("testSuccessfulCall()");
+
+				// Wait a bit for the operation to complete
+				await Task.Delay(1000);
+
+				// Test exception handling - this should NOT throw an exception in C# test code
+				// because the JavaScript should catch it
+				var exceptionResult = await hybridWebView.EvaluateJavaScriptAsync("testExceptionCall()");
+
+				// Wait a bit for the operation to complete
+				await Task.Delay(1000);
+
+				// Verify both methods were called
+				// Note: ThrowTestException should be the last method called since it executes after GetSuccessMessage
+				Assert.Equal("ThrowTestException", invokeJavaScriptTarget.LastMethodCalled);
+			});
+
 		[Fact]
 		public Task InvokeDotNetExceptionPreservesStackTrace() =>
 			RunTest("invokedotnetexceptiontests.html", async (hybridWebView) =>
@@ -698,6 +723,19 @@ public void Invoke_ThrowsCustomException()
 				throw new TestCustomException("Custom exception for testing", 42);
 			}
 
+			// Simple demo methods
+			public string GetSuccessMessage()
+			{
+				UpdateLastMethodCalled();
+				return "Method called successfully!";
+			}
+
+			public string ThrowTestException(string parameter)
+			{
+				UpdateLastMethodCalled();
+				throw new InvalidOperationException($"This is a test exception with parameter: {parameter}");
+			}
+
 			private void UpdateLastMethodCalled([CallerMemberName] string methodName = null)
 			{
 				LastMethodCalled = methodName;
diff --git a/src/Controls/tests/DeviceTests/Resources/Raw/HybridTestRoot/exceptiondemo.html b/src/Controls/tests/DeviceTests/Resources/Raw/HybridTestRoot/exceptiondemo.html
@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Exception Handling Test</title>
+    <script src="scripts/HybridWebView.js"></script>
+</head>
+<body>
+    <h1>HybridWebView Exception Handling Test</h1>
+    
+    <button id="testSuccess" onclick="testSuccessfulCall()">Test Successful Call</button>
+    <button id="testException" onclick="testExceptionCall()">Test Exception Call</button>
+    
+    <div id="results"></div>
+    
+    <script>
+        async function testSuccessfulCall() {
+            try {
+                const result = await window.HybridWebView.InvokeDotNet('GetSuccessMessage');
+                document.getElementById('results').innerHTML = '<p style="color: green;">Success: ' + result + '</p>';
+            } catch (error) {
+                document.getElementById('results').innerHTML = '<p style="color: red;">Unexpected error: ' + error.message + '</p>';
+            }
+        }
+        
+        async function testExceptionCall() {
+            try {
+                const result = await window.HybridWebView.InvokeDotNet('ThrowTestException', 'test parameter');
+                document.getElementById('results').innerHTML = '<p style="color: red;">ERROR: Should have thrown exception but got: ' + result + '</p>';
+            } catch (error) {
+                document.getElementById('results').innerHTML = 
+                    '<div style="color: orange;">' +
+                    '<p><strong>Exception caught successfully!</strong></p>' +
+                    '<p>Type: ' + (error.dotNetType || 'JavaScript Error') + '</p>' +
+                    '<p>Message: ' + error.message + '</p>' +
+                    '<p>Stack trace available: ' + (error.dotNetStackTrace ? 'Yes' : 'No') + '</p>' +
+                    '</div>';
+            }
+        }
+    </script>
+    
+    <div id="htmlLoaded"></div>
+</body>
+</html>
