c# 线程池RegisterWaitForSingleObject的一个Demo_c# registerwaitforsingleobject-优快云博客

本文通过一个Demo演示了如何在C#中利用线程池的RegisterWaitForSingleObject方法，实现异步等待信号量的释放，从而提高程序执行效率。

        static void Main(string[] args)
        {
            Console.WriteLine("first time 5s");
            RunOperations(TimeSpan.FromSeconds(5));
            Console.WriteLine("second time 7s");
            RunOperations(TimeSpan.FromSeconds(7));

            Console.ReadKey();
        }

        static void RunOperations(TimeSpan workerOperationTimeout)
        {
            using (var evt = new ManualResetEvent(false))
            {
                using (var cts = new CancellationTokenSource())
                {
                    Console.WriteLine("registering timeout operations...");
                    //当evt产生终止信号或超时 WorkerOperationWait()被执行
                    var worker = ThreadPool.RegisterWaitForSingleObject(
                        evt,
                        //System.Threading.WaitOrTimerCallback(object state, bool timedOut)
                        //evt每次超时或终止时回调此方法
                        (state, isTimeOut) => WorkerOperationWait(cts, isTimeOut),
                        null,
                        workerOperationTimeout,
                        true);
                    Console.WriteLine("starting long running operation...");
                    ThreadPool.QueueUserWorkItem(_ => WorkerOperation(cts.Token, evt));
                    Thread.Sleep(workerOperationTimeout.Add(TimeSpan.FromSeconds(2)));
                    worker.Unregister(evt);
                }
            }
        }
        
        static void WorkerOperation(CancellationToken token, ManualResetEvent evt)
        {
            for(int i = 0; i < 6; i ++)
            {
                if(token.IsCancellationRequested)
                {
                    //第一次，超时返回
                    return;
                }
                Thread.Sleep(TimeSpan.FromSeconds(1));
            }
            //第二次，产生信号
            evt.Set();
        }

        static void WorkerOperationWait(CancellationTokenSource cts, bool isTimeOut)
        {
            if(isTimeOut)
            {
                cts.Cancel();
                Console.WriteLine("worker operation timed out and was canceled.");
            }
            else
            {
                Console.WriteLine("worker operation succeded");
            }
        }

运行结果