我有这种播放声音的方法,当用户点击屏幕时,&当用户再次点击屏幕时,我希望它停止播放.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 ：)
解决方法
这是一个CancellationToken是什么.
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;
}
