C# 任务、线程、同步（二）

取消架构

1、Parallel.For()方法的取消

 1  static void CancelParallelLoop()
 2         {
 3             var cts = new CancellationTokenSource();
 4             cts.Token.Register(() => Console.WriteLine("*** token canceled"));
 5 
 6             cts.CancelAfter(200);
 7 
 8             try
 9             {
10                 ParallelLoopResult result = Parallel.For(0, 100, new ParallelOptions() { CancellationToken = cts.Token },
11                     x => {
12                         Console.WriteLine("loop {0} started", x);
13                         int sum = 0;
14                         for (int i = 0; i < 100; i++)
15                         {
16                             Thread.Sleep(2);
17                             sum += i;
18                         }
19                         Console.WriteLine("loop {0} finished", x);
20                     });
21             }
22             catch (Exception ex) 
23             {
24                 Console.WriteLine(ex.Message);
25             }
26         }

2、任务的取消

 1  static void CancelTask()
 2         {
 3             var cts = new CancellationTokenSource();
 4             cts.Token.Register(() => Console.WriteLine("*** task cancelled"));
 5             cts.CancelAfter(500);
 6 
 7             Task t1 = Task.Run(() => {
 8                 Console.WriteLine("in task ");
 9                 for (int i = 0; i < 20; i++)
10                 {
11                     Thread.Sleep(50);
12                     CancellationToken token = cts.Token;
13                     if(token.IsCancellationRequested)
14                     {
15                         Console.WriteLine("cancelling was requested, cancelling from within the task");
16                         token.ThrowIfCancellationRequested();
17                         break;
18                     }
19                     Console.WriteLine("in loop");
20                 }
21                 Console.WriteLine("task finished without cancellation");
22             },cts.Token);
23             try
24             {
25                 t1.Wait();
26             }
27             catch (AggregateException ex)
28             {
29                 Console.WriteLine("exception: {0}, {1}", ex.GetType().Name, ex.Message);
30                 foreach (var innerException in ex.InnerExceptions)
31                 {
32                     Console.WriteLine("inner excepion: {0}, {1}", ex.InnerException.GetType().Name, ex.InnerException.Message);
33                 }
34             }
35         }