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 = ;
             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();
                 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;
         }
     }