在应用程序的主线程中.刚刚启动BackgroundWork.

if (backgroundWorker1.IsBusy != true)
    {
        // Start the asynchronous operation.
        backgroundWorker1.RunWorkerAsync();
    }

然后它会触发DoWork事件.所以我们可以在那里做点什么.

private void backgroundWorker1_DoWork(object sender,DoWorkEventArgs e)
{
    BackgroundWorker worker = sender as BackgroundWorker;
    ......
    // report progress.
    worker.ReportProgress(iProgress);
    ....
}

然后我们只需要处理ProgressChanged事件以显示BackgroundWorker进度.

private void backgroundWorker1_ProgressChanged(object sender,ProgressChangedEventArgs e)
{
    //show progress.   
    resultLabel.Text = (e.ProgressPercentage.ToString() + "%");
}

DoWork完成或发生异常后.将触发RunWorkerCompleted事件.

这是我对这个事件处理的问题.请帮助审查它们.谢谢.

我注意到RunWorkerCompletedEventArgs中有一个名为’Result’的属性,它用于什么？我怎么用呢？

是否有可能接收我的自定义异常消息而不是e.error？如果有,如何制作？

private void backgroundWorker1_RunWorkerCompleted(object sender,RunWorkerCompletedEventArgs e)
{
    if (e.Cancelled == true)
    {
        resultLabel.Text = "Canceled!";
    }
    else if (e.Error != null)
    {
        resultLabel.Text = "Error: " + e.Error.Message;
    }
    else
    {
        resultLabel.Text = e.Result.ToString();
    }
}