C# backgroundWorker停不了了,backgroundWorker +串口

Question

程序里用了backgroundWorker来不停的读取串口数据的操作，         /// <summary>
        /// 接收各种数据
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void readAD_DoWork(object sender, DoWorkEventArgs e)
        {
            try
            {
                while (read)
                {
                    if (comport.IsOpen)
                    {
                        Thread.Sleep(10);
                        int n = comport.BytesToRead;
                        if (n > 0)
                        {
                            byte[] buf = new byte[n];                            comport.Read(buf, 0, n);
                            buffs.AddRange(buf);                            contin = true;
                            while (contin && buffs.Count >= 3)
                            {
                                deleData(buffs);
                            }
                        }
                    }
                }
            }
            catch (Exception ex) { StatusLabel.Text = ex.Message; }
        }
关闭程序的时候 ，我把read 设置为false
   private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            Properties.Settings.Default.Save();//使用Save方法保存更改、   
            read = false;
            while (readAD.IsBusy) { }
        }
但是这里判断这个backgroundworker，一直都没关闭，程序就死在那里了！！也许你会说，doWork里面的 while (contin && buffs.Count >= 3)
                            {
                                deleData(buffs);
                            }
可能一直，没退出，但是，可以肯定的是，现在完全没进入这个里面的while
为啥关闭不了！！！！
疑惑求解

Answer 1

 Properties.Settings.Default.Save()这个执行了没有？

Answer 2

执行了啊，调试的时候 就发现read = false;
            while (readAD.IsBusy) { }
这里的while一直没有判断到 readAD.isBusy = false，然后程序就死在那里了

Answer 3

while为什么不加上
else
 break; 

Answer 4

 while (read)
                {
                    if (comport.IsOpen)
                    {
                        Thread.Sleep(10);
                        int n = comport.BytesToRead;
                        if (n > 0)
                        {
                            byte[] buf = new byte[n];                            comport.Read(buf, 0, n);
                            buffs.AddRange(buf);                            contin = true;
                            while (contin && buffs.Count >= 3)
                            {
                                deleData(buffs);
                            }
                        }
                      else
                        break;
                    }
                  else
                   break;
                }

Answer 5

你用过while... else???我break了，还怎么不停的读取，我只是要在关闭窗口的时候 才让它停下来！