1 static void Main(string[] args)
2 {
3
4 var tasks = new List<Task<int>>();
5 CancellationTokenSource source = new CancellationTokenSource();
6 CancellationToken token = source.Token;
7 // Define a delegate that prints and returns the system tick count
8 Func<object, int> action = (object obj) =>
9 {
10 int i = (int)obj;
11
12 // Make each thread sleep a different time in order to return a different tick count
13 Thread.Sleep(i * 100);
14
15 // The tasks that receive an argument between 2 and 5 throw exceptions
16 if (2 <= i && i <= 5)
17 {
18 if (token.IsCancellationRequested)
19 token.ThrowIfCancellationRequested();
20 //source.Cancel();
21 // if (token.IsCancellationRequested)
22 //
23 // throw new AggregateException("SIMULATED EXCEPTION");
24 }
25
26 int tickCount = Environment.TickCount;
27 Console.WriteLine("Task={0}, i={1}, TickCount={2}, Thread={3}", Task.CurrentId, i, tickCount, Thread.CurrentThread.ManagedThreadId);
28
29 return tickCount;
30 };
31
32 // Construct started tasks
33 for (int i = 0; i < 10; i++)
34 {
35 int index = i;
36 //tasks.Add(Task<int>.Factory.StartNew(action, index, source.Token));
37 if (2 <= i && i <= 5)
38 {
39 tasks.Add(Task<int>.Factory.StartNew(action, index, source.Token));
40 }
41 else {
42 tasks.Add(Task<int>.Factory.StartNew(action, index));
43 }
44
45 }
46
47 try
48 {
49 // Wait for all the tasks to finish.
50 //
51 //
52 Task.WaitAny(tasks.ToArray());
53 source.Cancel();
54 Thread.Sleep(5000);
55
56 foreach (var t in tasks)
57 {
58 Console.WriteLine(" Task {0}: {1}", t.Id, t.Status);
59 }
60 // We should never get to this point
61 Console.WriteLine("WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED.");
62 }
63 catch (AggregateException e)
64 {
65 foreach (Exception ea in e.InnerExceptions)
66 {
67 if (ea is TaskCanceledException)
68 Console.WriteLine("Unable to compute mean: {0}",
69 ((TaskCanceledException)ea).Message);
70 else
71 Console.WriteLine("Exception: " + e.GetType().Name);
72 }
73 Console.WriteLine("\nThe following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)");
74 for (int j = 0; j < e.InnerExceptions.Count; j++)
75 {
76 Console.WriteLine("\n-------------------------------------------------\n{0}", e.InnerExceptions[j].ToString());
77 }
78 }
79 finally
80 {
81 source.Dispose();
82 }
83 }
