假设我有以下Start和Cancel事件处理程序.我如何知道触发取消的人是谁？
@H_403_2@private CancellationTokenSource cts;
private async void OnStartClick(object sender,RoutedEventArgs e)
{
try
{
cts = new CancellationTokenSource();
cts.CancelAfter(5000);
await Task.Delay(10000,cts.Token);
}
catch (TaskCanceledException taskCanceledException)
{
??? How do i know who canceled the task here ???
}
}
private void OnCancelClick(object sender,RoutedEventArgs e)
{
cts.Cancel();
cts.Dispose();
}
解决方法
无论是否单击了取消按钮,都存储在字段中：
@H_403_2@bool hasUserCancelled = false;
并在开始之前重置此字段：
@H_403_2@hasUserCancelled = false; cts = new CancellationTokenSource(); cts.CancelAfter(5000);在取消按钮单击处理程序中设置它：
@H_403_2@private void OnCancelClick(object sender,RoutedEventArgs e) { hasUserCancelled = true; cts.Cancel(); cts.Dispose(); }您想要的信息现在可以在catch中找到：
@H_403_2@catch (TaskCanceledException taskCanceledException) { Debug.WriteLine(new { hasUserCancelled }); }