// DeadLockSample.cs
// 分析一下为什么会发生死锁？

using System;using System.Threading;public class Test{    static readonly object firstLock = new object();    static readonly object secondLock = new object();        static void Main()    {        new Thread(new ThreadStart(ThreadJob)).Start();                // Wait until we're fairly sure the other thread        // has grabbed firstLock        Thread.Sleep(500);                Console.WriteLine ("Locking secondLock");        lock (secondLock)        {            Console.WriteLine ("Locked secondLock");            Console.WriteLine ("Locking firstLock");            lock (firstLock)            {                Console.WriteLine ("Locked firstLock");            }            Console.WriteLine ("Released firstLock");        }        Console.WriteLine("Released secondLock");    }        static void ThreadJob()    {        Console.WriteLine ("\t\t\t\tLocking firstLock");        lock (firstLock)        {            Console.WriteLine("\t\t\t\tLocked firstLock");            // Wait until we're fairly sure the first thread            // has grabbed secondLock            Thread.Sleep(1000);            Console.WriteLine("\t\t\t\tLocking secondLock");            lock (secondLock)            {                Console.WriteLine("\t\t\t\tLocked secondLock");            }            Console.WriteLine ("\t\t\t\tReleased secondLock");        }        Console.WriteLine("\t\t\t\tReleased firstLock");    }}
Locking firstLock
Locked firstLock 
Locking secondLock 
Locked secondLock 
Locking firstLock Locking secondLock

因应之道，使用Queue和Monitor:

//QueueMonitorThread.cs

using System;using System.Collections;using System.Threading;public class Test{    static ProducerConsumer queue;        static void Main()    {        queue = new ProducerConsumer();        new Thread(new ThreadStart(ConsumerJob)).Start();                Random rng = new Random(0);        for (int i=0; i < 10; i++)        {            Console.WriteLine ("Producing {0}", i);            queue.Produce(i);            Thread.Sleep(rng.Next(1000));        }    }        static void ConsumerJob()    {        // Make sure we get a different rando