Like Damien_The_Unbeliever mentioned, the Async CTP includes Task.Delay
. Fortunately, we have Reflector:
public static class TaskEx
{
static readonly Task _sPreCompletedTask = GetCompletedTask();
static readonly Task _sPreCanceledTask = GetPreCanceledTask();
public static Task Delay(int dueTimeMs, CancellationToken cancellationToken)
{
if (dueTimeMs < -1)
throw new ArgumentOutOfRangeException("dueTimeMs", "Invalid due time");
if (cancellationToken.IsCancellationRequested)
return _sPreCanceledTask;
if (dueTimeMs == 0)
return _sPreCompletedTask;
var tcs = new TaskCompletionSource<object>();
var ctr = new CancellationTokenRegistration();
var timer = new Timer(delegate(object self)
{
ctr.Dispose();
((Timer)self).Dispose();
tcs.TrySetResult(null);
});
if (cancellationToken.CanBeCanceled)
ctr = cancellationToken.Register(delegate
{
timer.Dispose();
tcs.TrySetCanceled();
});
timer.Change(dueTimeMs, -1);
return tcs.Task;
}
private static Task GetPreCanceledTask()
{
var source = new TaskCompletionSource<object>();
source.TrySetCanceled();
return source.Task;
}
private static Task GetCompletedTask()
{
var source = new TaskCompletionSource<object>();
source.TrySetResult(null);
return source.Task;
}
}