如何从线程更新表单

时间:2014-06-09 06:51:54

标签: c# multithreading

我正在使用mod总线协议从电路板上检索数据。现在我想一直以窗口形式更新数据。但标签只在我点击按钮时更新,我的编码有问题吗?

private void Call(){

        do
        {
            RequestData(); //get data from mod bus 
            run(a.ToString());


        } while (operation);

    }

    delegate void CallMethod(string Data);

    private void run(string data) {

        if (this.labelO2.InvokeRequired)
        {
            SetRichBoxCallBack d = new SetRichBoxCallBack(run);
            this.Invoke(d, new object[] { data });
        }
        else {
            labelO2.Text = data;
        }

    }
    Thread thread;
    private void button1_Click(object sender, EventArgs e)
    {

        thread = new Thread(new ThreadStart(Call));
        thread.Start();

    }
   public void RequestData()
    {

        if (WriteSerialPort(setMessage, 0, 8))
        {
            Thread.Sleep(1000);
            for (i = 0; i < 19; i++)
            {

                MM[i] = (byte)serialPortBoard.ReadByte();


            }

            a = MM[11] << 8 | MM[12];
            b = (int)MM[13] << 8 | MM[14];


        }

    }

1 个答案:

答案 0 :(得分:0)

对UI更新的调用应该包含在InvokeRequired ...模式中 - 而不是从端口获取数据。此外,InvokeRequired...模式也缺失。

delegate void UIUpdate(object a, object b);

public void RequestData() {
  ...
  // set type and real value here ;)
  object a = null, b = null;
  var call = new UIUpdate((pa,pb) => {
      labelBin.Text = pa.ToString();
      labelO2.Text = pb.ToString();
  });
  if (this.InvokeRequired) {
    this.Invoke(call, a, b);
  } else {
    call.Invoke(a, b);
  }      
}

private void button1_Click(object sender, EventArgs e) {
  new Thread(() => {
    do {
      RequestData();  // get the data from mod bus protocol
    } while (operation);
  }).Start();    
}

修改

此外,应该只有一个读者线程;哪个会读;不要在一个线程中写/读。读者线程应该在表单加载或表单构造函数中启动。

WriteSerialPort(setMessage, 0, 8)

应该在按钮点击时直接调用,而read应该始终在单个(单独)线程中。