一个线程在执行的过程中，可能调用另一个线程，前者可以称为调用线程，后者成为被调用线程。

Thread.Join方法的使用场景：调用线程挂起，等待被调用线程执行完毕后，继续执行。

如下案列:

当NewThread调用Join方法的时候，MainThread就被停止执行，直到NewThread线程执行完毕,才会接着再去执行。(转载)

static void Main(string[] args)
        {
            Thread.CurrentThread.Name = "MainThread";

            Thread newThread = new Thread(new ThreadStart(Program.ThreadFuncOne));
            newThread.Name = "NewThread";

            for (int j = 0; j < 20; j++)
            {
                if (j == 10)
                {
                    newThread.Start();
                    newThread.Join();
                }
                else
                {
                    Console.WriteLine(Thread.CurrentThread.Name + "   j =  " + j);
                }
            }
            Console.Read();
        }
    

        private static void ThreadFuncOne()
        {
            for (int i = 0; i < 10; i++)
            {
                Console.WriteLine(Thread.CurrentThread.Name + "   i =  " + i);
            }
            Console.WriteLine(Thread.CurrentThread.Name + " has finished");
        }