how to dispose the BlazorWebView in WPF blazor hybrid application?

William Liu 266

I have a usercontrol which contains BlazorWebView control. After load/unload this usercontrol several times, I find there are more and more Microsoft Edge WebView2 appear in Windows task manager. I guess it was caused by the unreleased BlazorWebView resource. I also find the BlazorWebview is IAsyncDisposable, does it mean we should dispose it after using it? If so, please provide a demo to show how to dispose it.

I tried the following codes, it seems the code release the WebView2 resource sometime, but it will crush the WPF application if I load/unload the usercontrol too frequently.

public sealed partial class HomeView
{
    public HomeView()
    {
        InitializeComponent();

        Unloaded += HomeView_Unloaded;
    }

    private async void HomeView_Unloaded(object sender, System.Windows.RoutedEventArgs e)
    {
        await BlazorWebView.DisposeAsync();
    }
}

Hui Liu-MSFT 38,256 Reputation points Microsoft Vendor

2024-04-08T05:58:29.35+00:00
Hi,@William Liu. Welcome to Microsoft Q&A.

The BlazorWebView control should be disposed of properly to release its resources, especially if you are loading and unloading the user control multiple times.

However, directly calling DisposeAsync() in the Unloaded event handler may not be sufficient, as it may cause issues if the control is being unloaded and loaded frequently.

One approach is to maintain a flag to track whether the BlazorWebView control has been disposed of, and then dispose of it only if it has not been disposed of previously. You could try the following code to see if it helps.

public sealed partial class HomeView { private bool isDisposed = false; public HomeView() { InitializeComponent(); Unloaded += HomeView_Unloaded; } private async void HomeView_Unloaded(object sender, System.Windows.RoutedEventArgs e) { if (!isDisposed) { await DisposeBlazorWebViewAsync(); isDisposed = true; } } private async Task DisposeBlazorWebViewAsync() { if (BlazorWebView != null) { await BlazorWebView.DisposeAsync(); BlazorWebView = null; } } }

If the problem persists, you can also ask question on GitHub.
William Liu 266 Reputation points

2024-04-08T07:06:41.4566667+00:00

Thanks, I get your point now.