Does Task.Wait(int) stop the task if the timeout elapses without the task finishing?

Question

I have a task and I expect it to take under a second to run but if it takes longer than a few seconds I want to cancel the task.

For example:

Task t = new Task(() =>
        {
            while (true)
            {
                Thread.Sleep(500);
            }
        });
t.Start();
t.Wait(3000);

Notice that after 3000 milliseconds the wait expires. Was the task canceled when the timeout expired or is the task still running?

Answer 1

If you want to cancel a Task, you should pass in a CancellationToken when you create the task. That will allow you to cancel the Task from the outside. You could tie cancellation to a timer if you want.

To create a Task with a Cancellation token see this example:

var tokenSource = new CancellationTokenSource();
var token = tokenSource.Token;

var t = Task.Factory.StartNew(() => {
    // do some work
    if (token.IsCancellationRequested) {
        // Clean up as needed here ....
    }
    token.ThrowIfCancellationRequested();
}, token);

To cancel the Task call Cancel() on the tokenSource.