Question

我创建了一个GUI（winforms）并添加了一个后台工作程序以在一个单独的线程中运行。后台工作人员需要不断更新2个标签。 backgroundworker线程应该以button1单击开始并永远运行。

    class EcuData 
    {
        public int RPM { get; set; }
        public int MAP { get; set; }
    }

    private void button1_Click(object sender, EventArgs e)
    {
        EcuData data = new EcuData
        {
            RPM = 0,
            MAP = 0
        };
        BackWorker1.RunWorkerAsync(data);
    }

    private void BackWorker1_DoWork(object sender, DoWorkEventArgs e)
    {
        EcuData argumentData = e.Argument as EcuData;
        int x = 0;
        while (x<=10)
        {
            //
            // Code for reading in data from hardware.
            //
            argumentData.RPM = x;           //x is for testing only!
            argumentData.MAP = x * 2;       //x is for testing only!
            e.Result = argumentData;
            Thread.Sleep(100);
            x++;
       }
    private void BackWorker1_RunWorkerCompleted_1(object sender,  RunWorkerCompletedEventArgs e)
    {
        EcuData data = e.Result as EcuData;
        label1.Text = data.RPM.ToString();
        label2.Text = data.MAP.ToString();
    }
}

上面的代码刚刚在后台工作完成他的工作时更新了GUI，而这不是我正在寻找的。

Answer 1

您需要查看BackgroundWorker.ReportProgess。

您可以使用它定期将对象传回主线程中的方法，该方法可以为您更新标签。

Answer 2

您可以使用System.Threading.Timer并通过调用主窗体上的BeginInvoke从Timer的回调方法更新UI。

uiUpdateTimer = new System.Threading.Timer(new TimerCallback(
            UpdateUI), null, 200, 200);

private void UpdateUI(object state)
{
    this.BeginInvoke(new MethodInvoker(UpdateUI));
}

private void UpdateUI()
{
    // modify labels here
}

Answer 3

class EcuData
    {
        public int RPM { get; set; }
        public int MAP { get; set; }
    }

    private void button1_Click(object sender, EventArgs e)
    {
        EcuData data = new EcuData
        {
            RPM = 0,
            MAP = 0
        };
        BackWorker1.RunWorkerAsync(data);
    }

    private void BackWorker1_DoWork(object sender, DoWorkEventArgs e)
    {
        EcuData argumentData = e.Argument as EcuData;
        int x = 0;
        while (x<=10)
        {
            e.Result = argumentData;
            Thread.Sleep(100);
            this.Invoke((MethodInvoker)delegate
            {
                label1.Text = Convert.ToString(argumentData.RPM = x);           //send hardware data later instead, x is for testing only!
                label2.Text = Convert.ToString(argumentData.MAP = x * 2);       //send hardware data later instead, x is for testing only!
            });
            x++;
       }
    }

这有效，但这是正确的做法吗？

C＃从后台工作者不断更新GUI

3 个答案: