互斥锁(Mutex)
互斥锁是一个互斥的同步对象,意味着同一时间有且仅有一个线程可以获取它。
互斥锁可适用于一个共享资源每次只能被一个线程访问的情况
函数:
//创建一个处于未获取状态的互斥锁
Public Mutex();
//如果owned为true,互斥锁的初始状态就是被主线程所获取,否则处于未获取状态
Public Mutex(bool owned);
如果要获取一个互斥锁。应调用互斥锁上的WaitOne()方法,该方法继承于Thread.WaitHandle类
它处于等到状态直至所调用互斥锁可以被获取,因此该方法将组织住主调线程直到指定的互斥锁可用,如果不需要拥有互斥锁,用ReleaseMutex方法释放,从而使互斥锁可以被另外一个线程所获取。
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using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading; namespace MyTTCon { class shareRes { public static int count = 0; public static Mutex mutex = new Mutex(); } class IncThread { int number; public Thread thrd; public IncThread( string name, int n) { thrd = new Thread( this .run); number = n; thrd.Name = name; thrd.Start(); } void run() { Console.WriteLine(thrd.Name + "正在等待 the mutex" ); //申请 shareRes.mutex.WaitOne(); Console.WriteLine(thrd.Name + "申请到 the mutex" ); do { Thread.Sleep(1000); shareRes.count++; Console.WriteLine( "In " + thrd.Name + "ShareRes.count is " + shareRes.count); number--; } while (number > 0); Console.WriteLine(thrd.Name + "释放 the nmutex" ); // 释放 shareRes.mutex.ReleaseMutex(); } } class DecThread { int number; public Thread thrd; public DecThread( string name, int n) { thrd = new Thread( this .run); number = n; thrd.Name = name; thrd.Start(); } void run() { Console.WriteLine(thrd.Name + "正在等待 the mutex" ); //申请 shareRes.mutex.WaitOne(); Console.WriteLine(thrd.Name + "申请到 the mutex" ); do { Thread.Sleep(1000); shareRes.count--; Console.WriteLine( "In " + thrd.Name + "ShareRes.count is " + shareRes.count); number--; } while (number > 0); Console.WriteLine(thrd.Name + "释放 the nmutex" ); // 释放 shareRes.mutex.ReleaseMutex(); } } class Program { static void Main( string [] args) { IncThread mthrd1 = new IncThread( "IncThread thread " , 5); DecThread mthrd2 = new DecThread( "DecThread thread " , 5); mthrd1.thrd.Join(); mthrd2.thrd.Join(); } } } |