只需停止异步方法即可

我有这种播放声音的方法，当用户点击屏幕时，我希望它在用户再次点击屏幕时停止播放。 但问题是“DoSomething（）”方法不会停止，它会一直持续到完成。

bool keepdoing = true; private async void ScreenTap(object sender, System.Windows.Input.GestureEventArgs e) { keepdoing = !keepdoing; if (!playing) { DoSomething(); } } private async void DoSomething() { playing = true; for (int i = 0; keepdoing ; count++) { await doingsomething(text); } playing = false; } 

任何帮助将不胜感激。
谢谢 ：）

Answer 1

这就是CancellationToken的用途。

 CancellationTokenSource cts; private async void ScreenTap(object sender, System.Windows.Input.GestureEventArgs e) { if (cts == null) { cts = new CancellationTokenSource(); try { await DoSomethingAsync(cts.Token); } catch (OperationCanceledException) { } finally { cts = null; } } else { cts.Cancel(); cts = null; } } private async Task DoSomethingAsync(CancellationToken token) { playing = true; for (int i = 0; ; count++) { token.ThrowIfCancellationRequested(); await doingsomethingAsync(text, token); } playing = false; }