How do I abort/cancel TPL Tasks?

Question

In a thread, I create some System.Threading.Task and start each task.

When I do a .Abort() to kill the thread, the tasks are not aborted.

Answer 1

Aborting a Task is easily possible if you capture the thread in which the task is running in. Here is an example code to demonstrate this:

void Main()
{
    Thread thread = null;

    Task t = Task.Run(() => 
    {
        //Capture the thread
        thread = Thread.CurrentThread;

        //Simulate work (usually from 3rd party code)
        Thread.Sleep(1000);

        //If you comment out thread.Abort(), then this will be displayed
        Console.WriteLine("Task finished!");
    });

    //This is needed in the example to avoid thread being still NULL
    Thread.Sleep(10);

    //Cancel the task by aborting the thread
    thread.Abort();
}

I used Task.Run() to show the most common use-case for this - using the comfort of Tasks with old single-threaded code, which does not use the CancellationTokenSource class to determine if it should be canceled or not.