强制将任何任务附加到父任务
本文关键字:任务 任何 | 更新日期: 2023-09-27 18:20:01
我正在尝试创建一个扩展方法,使任何任务都附加到父任务。
扩展码:
internal static class TaskHelpers
{
public static Task AttachToParrent(this Task task)
{
var tsc = new TaskCompletionSource<Task>(task.CreationOptions & TaskCreationOptions.AttachedToParent);
task.ContinueWith(_ => tsc.TrySetResult(task), TaskContinuationOptions.OnlyOnRanToCompletion);
task.ContinueWith(t => tsc.TrySetException(task.Exception ?? new AggregateException(new ApplicationException("Unknown"))), TaskContinuationOptions.OnlyOnFaulted);
task.ContinueWith(t => tsc.TrySetCanceled(), TaskContinuationOptions.OnlyOnCanceled);
return tsc.Task.Unwrap();
}
}
测试代码:
static void Main(string[] args)
{
var cancellationTokenSource = new CancellationTokenSource();
var task1 = Task.Factory.StartNew(() =>
{
var task2 = Task.Factory.StartNew(() =>
{
for (int i = 0; i < 5; i++)
{
if (!cancellationTokenSource.IsCancellationRequested)
{
Console.WriteLine(i);
Thread.Sleep(5000);
}
else
{
Console.WriteLine("Loop cancelled.");
break;
}
}
}, cancellationTokenSource.Token).AttachToParrent();
var task3 = Task.Factory.StartNew(() =>
{
for (int i = 0; i < 5; i++)
{
if (!cancellationTokenSource.IsCancellationRequested)
{
Console.WriteLine(i*10);
Thread.Sleep(5000);
}
else
{
Console.WriteLine("Loop cancelled.");
break;
}
}
}, cancellationTokenSource.Token).AttachToParrent();
}, cancellationTokenSource.Token);
Console.WriteLine("Enter to cancel");
Console.ReadKey();
cancellationTokenSource.Cancel();
Console.WriteLine("Waiting To Be Cancelled");
task1.Wait();
Console.WriteLine("Task Cancelled");
Console.ReadKey();
}
父任务将立即取消,无需等待内部任务完成。我该如何解决它,作为一个输入,我得到了一个在父调度程序任务中执行的任务。我想执行任何附加到父级的任务。
仅在调用Task.Factory.StartNew
时提供TaskCreationOptions.AttachedToParent
(仅在创建子任务时):
var task2 = Task.Factory.StartNew(..., cancellationTokenSource.Token, TaskCreationOptions.AttachedToParent, TaskScheduler.Current);
有关附加/分离任务的更多信息:请参阅MSDN
发现问题,问题在中
var tsc = new TaskCompletionSource<Task>(task.CreationOptions & TaskCreationOptions.AttachedToParent);
tsc,CreationOptions保留为nooptions。
已更改为
var tsc = new TaskCompletionSource<Task>(TaskCreationOptions.AttachedToParent);
现在一切正常。