后台工作人员-报告时间

本文关键字：时间 报告 工作人员 后台 | 更新日期: 2023-09-27 18:17:41

我有一个控制我的GUI，我想使可见的情况下，当我运行BackgroundWorkers(许多不同的操作)。其中一些操作的持续时间不到500毫秒，我觉得让控件在这么短的时间内可见是没有用的。因此，我想使控制可见，只有当一个BackgroundWorker已经工作了500ms。

后台工作人员-报告时间

在启动BGW的同时启动计时器:

    private void button1_Click(object sender, EventArgs e) {
        timer1.Enabled = true;
        backgroundWorker1.RunWorkerAsync();
    }
    private void timer1_Tick(object sender, EventArgs e) {
        timer1.Enabled = false;
        myControl1.Visible = true;
    }
    private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) {
        timer1.Enabled = myControl1.Visible = false;
    }

在BackgroundWorker上利用ReportProgress方法。您可以在状态参数中放置任何您想要的东西，然后执行相应的计算。

public class MyObject
{
    public DateTime TimeStarted {get; set;}
}

然后在ProgressChanged事件处理程序中…

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    if(DateTime.Now.Subtract(((MyObject)e.UserState).TimeStarted).TotalMilliseconds > 500)
    {
         //show your control
    }
}

你可以在BackgroundWorker中使用Timer，并在500ms后调用ReportProgress方法。

在UI线程中，你只需要处理ProgressChanged事件并根据需要显示/隐藏你的控件。

public partial class Form1 : Form
{
    /// <summary>
    /// Timer.
    /// </summary>
    private Timer timer = new Timer();
    /// <summary>
    /// Initializes a new instance of the <see cref="Form1"/> class.
    /// </summary>
    public Form1()
    {
        InitializeComponent();
        backgroundWorker1.WorkerReportsProgress = true;
        backgroundWorker1.DoWork += BackgroundWorker1DoWork;
        backgroundWorker1.ProgressChanged += BackgroundWorker1ProgressChanged;
        timer.Interval = 500;
        timer.Tick += TimerTick;
    }
    /// <summary>
    /// Handles the Tick event of the timer control.
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
    void TimerTick(object sender, EventArgs e)
    {
        timer.Enabled = false;
        backgroundWorker1.ReportProgress(99);
    }
    /// <summary>
    /// Handles the Click event of the button1 control.
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
    private void Button1Click(object sender, EventArgs e)
    {
        timer.Enabled = true;
        backgroundWorker1.RunWorkerAsync();
    }
    /// <summary>
    /// Handles the DoWork event of the backgroundWorker1 control.
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="System.ComponentModel.DoWorkEventArgs"/> instance containing the event data.</param>
    private void BackgroundWorker1DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        // Do your work...
        Thread.Sleep(2000);
    }
    /// <summary>
    /// Handles the ProgressChanged event of the backgroundWorker1 control.
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="System.ComponentModel.ProgressChangedEventArgs"/> instance containing the event data.</param>
    private void BackgroundWorker1ProgressChanged(object sender, ProgressChangedEventArgs e)
    {
        label1.Visible = (e.ProgressPercentage == 99);
    }
}
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