通过set和waitOne来控制子线程的运行和停止

 public partial class Form1 : Form
    {
     
        //自动重置事件类     
        //主要用到其两个方法 WaitOne() 和 Set() , 前者阻塞当前线程，后者通知阻塞线程继续往下执行   
        AutoResetEvent autoEvent = new AutoResetEvent(false);

        public Form1()
        {
            InitializeComponent();
        }
        public static bool _stop=true;
        private void button3_Click(object sender, EventArgs e)
        {
            int i = 0;
            Thread NewThread = new Thread(Run);
            NewThread.Start(i);
        }
        private void Run(object i)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
            int j = (int)i;
           
            while (true)
            {
                j++;
                Thread.Sleep(1000);
                label1.Text = j.ToString();
                label1.Refresh();
                if(_stop)
                   autoEvent.WaitOne();  //阻塞当前线程，等待通知以继续执行 
            }
        
        }

        private void button1_Click(object sender, EventArgs e)
        {
            autoEvent.Set(); //通知阻塞的线程继续执行  
            _stop = false;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            _stop = true;
        }
    }