多线程lock(this.lockObject)的作用验证 Anny

namespace MultiThread
{
    class SynchronizationThreadsExample
    {
        private int counter = 0; //被多个线程共享
        private object lockObject = new object();
        static void Main(string[] args)
        {
            SynchronizationThreadsExample STE = new SynchronizationThreadsExample();
            STE.ThreadFunction();
            Console.ReadLine();
        }
        public void ThreadFunction()
        {
            Thread DummyThread = new Thread(new ThreadStart(SomeFunction));
            DummyThread.IsBackground = true;
            DummyThread.Name = "First Thread";
            DummyThread.Start();
            Console.WriteLine("Started thread {0}", DummyThread.Name);
            Thread DummyPriorityThread = new Thread(new ThreadStart(SomeFunction));
            DummyPriorityThread.IsBackground = true;
            DummyPriorityThread.Name = "Second Thread";
            DummyPriorityThread.Start();
            Console.WriteLine("Started thread {0}", DummyPriorityThread.Name);
            DummyThread.Join();
            DummyPriorityThread.Join();
        }
        public void SomeFunction()
        {
            try
            {
                while (counter < 10)
                {
                        counter++;
                        Thread.Sleep(1);
                        Console.WriteLine("Thread . SomeFunction-counter: " + Thread.CurrentThread.Name + counter);               

　　　　　　}
            }
            catch (ThreadInterruptedException Ex)
            {
                Console.WriteLine("Exception in thread " + Thread.CurrentThread.Name);
            }
            finally
            {
                Console.WriteLine("Thread Exiting. " + Thread.CurrentThread.Name);
            }
        }
    }
}

运行结果：

Started thread First Thread
Thread . SomeFunction-counter: First Thread1
Thread . SomeFunction-counter: First Thread2
Thread . SomeFunction-counter: First Thread3
Started thread Second Thread
Thread . SomeFunction-counter: First Thread4
Thread . SomeFunction-counter: First Thread5
Thread . SomeFunction-counter: First Thread7
Thread . SomeFunction-counter: Second Thread7
Thread . SomeFunction-counter: First Thread9
Thread . SomeFunction-counter: Second Thread9
Thread Exiting. Second Thread
Thread . SomeFunction-counter: First Thread10
Thread Exiting. First Thread

将上边黄色代码加锁，具体如下，结果将发生变化：

　　　　　　　lock(this.lockObject)
                   {
                        counter++;
                        Thread.Sleep(1);
                        Console.WriteLine("Thread . SomeFunction-counter: " + Thread.CurrentThread.Name + counter);
                   }

运行结果如下：

Started thread First Thread
Thread . SomeFunction-counter: First Thread1
Thread . SomeFunction-counter: First Thread2
Started thread Second Thread
Thread . SomeFunction-counter: First Thread3
Thread . SomeFunction-counter: First Thread4
Thread . SomeFunction-counter: Second Thread5
Thread . SomeFunction-counter: Second Thread6
Thread . SomeFunction-counter: Second Thread7
Thread . SomeFunction-counter: Second Thread8
Thread . SomeFunction-counter: Second Thread9
Thread . SomeFunction-counter: First Thread10
Thread Exiting. First Thread
Thread . SomeFunction-counter: Second Thread11
Thread Exiting. Second Thread