. Cooperative cancellation mode of NET4.0 thread pool

Just installed the VS2010RC version, experience. New cooperative cancellation mode for the NET4.0 thread pool.

Used. NET thread pool people know that once the code to execute to the thread pool to execute, we basically lost the code in the operation of the control ability. For example, if we want to cancel the execution of this code at some point, we have to think of another way. With. NET4.0 arrived, the problem was solved. NET4.0 introduces a new design pattern---Cooperative cancellation mode (cooperative cancellation).

. The System.Threading namespace of NET4.0 has two new members, one is the CancellationTokenSource class, the other is the cancellationtoken structure. The main members of the CancellationTokenSource class are as follows:

public　sealed　class　CancellationTokenSource　:　IDisposable 　{
public　CancellationTokenSource();
public　void　Dispose();
public　Boolean　IsCancellationRequested　{　get;　}
public　CancellationToken　Token　{　get;　}//CancellationToken结构
public　void　Cancel();
public　void　Cancel(Boolean　throwOnFirstException);
}

The CancellationToken structure code is roughly as follows:

　public　struct　CancellationToken
　　　　 {　
　　　　　　　　 public　Boolean　IsCancellationRequested　{　get; 　}
　　　　　　　　 public　void　ThrowIfCancellationRequested();
　　　　　　　　 //　当CancellationTokenSource取消时使用的信号量
　　　　　　　　 public　WaitHandle　WaitHandle　{　get;　}
　　　　　　　　 public　static　CancellationToken　None　{　get;　}
　　　　　　　　 public　Boolean　CanBeCanceled　{　get;　}
　　　　　　　　 public　CancellationTokenRegistration　Register (Action<Object>　callback,　Object　state,　Boolean　 useSynchronizationContext);
　　　　 }

Use the following code:

using System;
using System.Threading;
namespace Cooperativecancellation
{
Class program
{
static void Main (string[] args)
{
CancellationTokenSource cts = new Can Cellationtokensource ();
ThreadPool.QueueUserWorkItem (o => executeinthreadpool (CTS). Token));
Console.WriteLine ("Press <Enter> to cancel the operation");
Console.ReadLine ();
CTS. Cancel ();
Console.ReadLine ();
}
static void Executeinthreadpool (CancellationToken token)
{
Con Sole. WriteLine ("Enter in ThreadPool.");
while (!token). iscancellationrequested)
{
Console.Write (".");
Thread.Sleep (1000);
}
Console.WriteLine ("Operation is be cancel.");
}
}
}

The code is simple, I don't have to say much here. In short, with the cooperative cancellation model, we were right. NET thread pool, the execution of code has more control, it is a good function.