1  //调用QueueUserWorkItem
2 ThreadPool.QueueUserWorkItem(DoSomeThing, 5);
3 
4 //用任务来做相同的事情
5 Task.Run(() => DoSomeThing(5));      

 1 CancellationTokenSource cts = new CancellationTokenSource();
 2 Task<int> t = Task.Run<int>(() => Sum(cts.Token, 2000));
 3 Thread.Sleep(10);
 4 cts.Cancel();
 5 
 6 try
 7 {
 8     Console.WriteLine("The Sum is: " + t.Result);
 9 }
10 catch (AggregateException x)
11 {
12     //将任何OperationCanceledException对象都视为已处理
13     //使其中只包含未处理的异常
14      x.Handle(e => e is OperationCanceledException);
15 
16     //对未处理的异常进行处理
17     //TODO
18     //...
19     //...
20 
21     Console.WriteLine("Sum was canceled");
22 }

 1 static int Sum(CancellationToken ct,int n)
 2 {
 3     if (n > 1000)
 4     {
 5         throw new Exception("Value of n is too large.");
 6     }
 7 
 8     int sum = 0;
 9     for (int i = 1; i <= n; i++)
10     {
11         //如果CancellationTokenSource已取消(Cancel),
12         //下面代码将抛出"System.OperationCanceledException"异常
13         ct.ThrowIfCancellationRequested();
14         sum += i;
15     }
16     return sum;
17 }

 1 //Parallel的For方法
 2 for (int i = 0; i < 1000; i++)
 3 {
 4     DoWork(i);
 5 }
 6 Parallel.For(0, 1000, i => DoWork(i));
 7 
 8 //Parallel的ForEach方法
 9 int[] idCollection = new int[] {1,2,3,4,5,6,7,8,9 };
10 foreach (var item in idCollection)
11 {
12     DoWork(item);
13 }
14 Parallel.ForEach(idCollection, item => DoWork(item));
15 
16 //Parallel的Invoke方法
17 Method1();
18 Method2();
19 Method3();
20 Parallel.Invoke(
21     () => Method1(),
22     () => Method2(),
23     () => Method3());