Deadlock --- 死鎖

A deadlock is a situation where an application locks up because two or more activities are waiting for each other to finish.

例子：

using System;

using System.Threading;


public class Simple {

    static object A = new object();

    static object B = new object();


    static void MethodA()
    {
        Console.WriteLine("Inside methodA");
        lock (A)
        {
            Console.WriteLine("MethodA: Inside LockA and Trying to enter LockB");
            Thread.Sleep(5000);           
            lock (B)
            {
                Console.WriteLine("MethodA: inside LockA and inside LockB");
                Thread.Sleep(5000);
            }
            Console.WriteLine("MethodA: inside LockA and outside LockB");
        }
        Console.WriteLine("MethodA: outside LockA and outside LockB");
    }

    static void MethodB()
    {
        Console.WriteLine("Inside methodB");
        lock (B)
        {
            Console.WriteLine("methodB: Inside LockB");
            Thread.Sleep(5000);
            lock (A)
            {
                Console.WriteLine("methodB: inside LockB and inside LockA");
                Thread.Sleep(5000);
            }
            Console.WriteLine("methodB: inside LockB and outside LockA");
        }
        Console.WriteLine("methodB: outside LockB and outside LockA");
    }

    public static void Main(String[] args)
    {

        Thread Thread1 = new Thread(MethodA);
        Thread Thread2 = new Thread(MethodB);
        Thread1.Start();
        Thread2.Start();
        Console.WriteLine("enter.....");
        Console.ReadLine();

    }
}