线程学习（四）Mutex使用

• 线程使用Mutex

  • Mutex 用于线程同步，也可用进程间同步

    using System;
    using System.Threading;
    
    namespace Pattern03
    {
        class Program
        {
    
            static int thread_num = 5;//线程数
            static AutoResetEvent autoReset = new AutoResetEvent(false);//标记线程池中执行情况
            static Resource resource = new Resource();
    
            static void Main(string[] args)
            {
    
                for (int i = 0; i < thread_num; i++)
                {
                    ThreadPool.QueueUserWorkItem(AsyncMethod, i);
                }
    
                autoReset.WaitOne();
                Console.WriteLine("all complete");
    
                Console.ReadKey();
            }
    
            static void AsyncMethod(object state)
            {
                resource.Access((int)state);
    
                if (Interlocked.Decrement(ref thread_num) == 0)//原子性操作变量 thread_num
                {
                    Console.WriteLine($"线程id:thread_num{Thread.CurrentThread.ManagedThreadId} 调用完成");
                    autoReset.Set();
                }
            }
    
        }
    
        class Resource
        {
            Mutex mutex = new Mutex();
            public void Access(int Num)
            {
                mutex.WaitOne();
                try
                {
                    //这段代码是线程安全的
    
                    Console.WriteLine($"线程id:{Thread.CurrentThread.ManagedThreadId} start the Accesss method ，num:{Num}");
                    Thread.Sleep(1000);//模拟耗时操作
                    Console.WriteLine($"线程id:{Thread.CurrentThread.ManagedThreadId} stop the Acess method");
    
                    //这段代码是线程安全的
                }
                finally
                {
                    mutex.ReleaseMutex();
                }
               
            }
        }
    }