[Blazor] Suppress JSDisconnectedException in IJSObjectReference.DisposeAsync (#64773)

Author: Copilot

src/JSInterop/Microsoft.JSInterop/src/Implementation/JSObjectReference.cs

@@ -104,7 +104,15 @@ public async ValueTask DisposeAsync()
         {
             Disposed = true;
 
-            await _jsRuntime.InvokeVoidAsync("DotNet.disposeJSObjectReferenceById", Id);
+            try
+            {
+                await _jsRuntime.InvokeVoidAsync("DotNet.disposeJSObjectReferenceById", Id);
+            }
+            catch (JSDisconnectedException)
+            {
+                // If the JavaScript runtime is disconnected, there's no need to dispose the JS object reference
+                // as the JS side is already gone. We can safely ignore this exception.
+            }
         }
     }
 

src/JSInterop/Microsoft.JSInterop/test/JSObjectReferenceTest.cs

@@ -66,6 +66,37 @@ public void JSInProcessObjectReference_Dispose_DisallowsFurtherInteropCalls()
         Assert.Throws<ObjectDisposedException>(() => jsObject.Invoke<object>("test", "arg1", "arg2"));
     }
 
+    [Fact]
+    public async Task JSObjectReference_DisposeAsync_IgnoresJSDisconnectedException()
+    {
+        // Arrange
+        var jsRuntime = new TestJSRuntimeThatThrowsJSDisconnectedException();
+        var jsObject = new JSObjectReference(jsRuntime, 0);
+
+        // Act & Assert - Should not throw
+        await jsObject.DisposeAsync();
+
+        // Verify dispose was attempted
+        Assert.Equal(1, jsRuntime.BeginInvokeJSInvocationCount);
+    }
+
+    [Fact]
+    public async Task JSObjectReference_DisposeAsync_IgnoresJSDisconnectedException_OnMultipleCalls()
+    {
+        // Arrange
+        var jsRuntime = new TestJSRuntimeThatThrowsJSDisconnectedException();
+        var jsObject = new JSObjectReference(jsRuntime, 0);
+
+        // Act & Assert - Should not throw on first call
+        await jsObject.DisposeAsync();
+
+        // Act & Assert - Should not throw on second call (no-op)
+        await jsObject.DisposeAsync();
+
+        // Verify dispose was only attempted once
+        Assert.Equal(1, jsRuntime.BeginInvokeJSInvocationCount);
+    }
+
     class TestJSRuntime : JSRuntime
     {
         public int BeginInvokeJSInvocationCount { get; private set; }
@@ -85,6 +116,26 @@ protected internal override void EndInvokeDotNet(DotNetInvocationInfo invocation
         }
     }
 
+    class TestJSRuntimeThatThrowsJSDisconnectedException : JSRuntime
+    {
+        public int BeginInvokeJSInvocationCount { get; private set; }
+
+        protected override void BeginInvokeJS(in JSInvocationInfo invocationInfo)
+        {
+            BeginInvokeJSInvocationCount++;
+            throw new JSDisconnectedException("JavaScript interop calls cannot be issued at this time. This is because the circuit has disconnected and is being disposed.");
+        }
+
+        protected override void BeginInvokeJS(long taskId, string identifier, [StringSyntax("Json")] string? argsJson, JSCallResultType resultType, long targetInstanceId)
+        {
+            throw new NotImplementedException();
+        }
+
+        protected internal override void EndInvokeDotNet(DotNetInvocationInfo invocationInfo, in DotNetInvocationResult invocationResult)
+        {
+        }
+    }
+
     class TestJSInProcessRuntime : JSInProcessRuntime
     {
         public int InvokeJSInvocationCount { get; private set; }