1 internal static class CancellationDemo
2 {
3 public static void Go()
4 {
5 //向应该被取消的CancellationToken发送信号
6 CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
7
8 ThreadPool.QueueUserWorkItem(o => Count(cancellationTokenSource.Token, 100));
9
10 //指定毫秒（2000）后取消操作
11 //cancellationTokenSource.CancelAfter(2000);
12
13 Console.WriteLine("Press <Enter> to cancel the operation.");
14
15 Console.ReadLine();
16
17 //如果Count方法已返回，Cancel无任何效果
18 cancellationTokenSource.Cancel();
19 //Cancel立即返回，方法从这里继续执行
20
21 Console.ReadLine();
22 }
23
24 private static void Count(CancellationToken cancellationToken, int countTo)
25 {
26 for (int i = 0; i < countTo; i++)
27 {
28 if (cancellationToken.IsCancellationRequested)
29 {
30 Console.WriteLine("Count is cancelled.");
31 break;
32 }
33 Console.WriteLine(i);
34 Thread.Sleep(200);
35 }
36 Console.WriteLine("Count is done.");
37 }
38 }
