创建线程并且启用

1、创建线程（全局）

  private Thread LookPictureThread;

2 创建启动线程的方法 （放在一起方便管理）

 private void StartThread()
        {
            if (LookPictureThread == null)
            {
                LookPictureThread = new Thread(new ThreadStart(lookPicture));
                LookPictureThread.IsBackground = true;
                LookPictureThread.Start();
            }
            
        }

3 启动线程   直接调用StartThread()方法即可