using System;

using System.Threading;

using System.Threading.Tasks;

public class Program

{

    static public void Main()

    {

        using (var cts = new CancellationTokenSource(100))

        {

            var t = Task.Run(() =>

                             {

                                 Thread.Sleep(1000);

                                 cts.Token.ThrowIfCancellationRequested();

                             }, cts.Token);

            Thread.Sleep(2000);

            Console.WriteLine(t.Status);

        }

        using (var cts = new CancellationTokenSource(100))

        {

            var t = Task.Run(() =>

                             {

                                 Thread.Sleep(1000);

                                 cts.Token.ThrowIfCancellationRequested();

                             });

            Thread.Sleep(2000);

            Console.WriteLine(t.Status);

        }

    }

}