使用backgroundworker时出错

Question

//这是我的代码

private void btnGenSumm_Click(object sender, EventArgs e)
{
    if (backgroundWorker1.IsBusy != true)
    {
        btnGenSumm.Enabled = false;
        btnExpSum.Enabled = false;
        btnClose.Enabled = false;
        pBox1.Visible = true;
        backgroundWorker1.RunWorkerAsync();
    }
}

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
        BackgroundWorker worker = sender as BackgroundWorker;
        loadSummSales(); // this is the process
        System.Threading.Thread.Sleep(50);
}

private void backgroundWorker1_RunWorkerCompleted(object sender, 
    RunWorkerCompletedEventArgs e)
{
        pBox1.Visible = false;
}

第一次单击时执行该过程没有错误，但是当我再次尝试单击命令按钮（btnGenSumm）以重复该过程时，出现错误“在执行createhandle时不能调用值处理”。，请帮助我有了这个。

Answer 1

在开始执行任务之前，我总是会创建一个新的工作人员。 这样可以避免这些问题。

private void btnGenSumm_Click(object sender, EventArgs e)
{
    // WorkerFactory creates your worker and hooks up the DoWork 
    // and RunWorkerCompleted events
    var backgroundWorker1 = WorkerFactory();

    // ...
    // Disable access to this Click event in the UI here

    backgroundWorker1.RunWorkerAsync();
}

private void backgroundWorker1_RunWorkerCompleted(
    object sender, 
    RunWorkerCompletedEventArgs e)
{
    // Re-enable access to the Click event in the UI here
}

使用这种方法，无法在工作进程运行时访问该工作进程，并且可以保证，只要用户单击该按钮，最后一个工作进程IsBusy完成，并且不会出现讨厌的IsBusy软糖。

更新

明确地， WorkerFactory做这样的事情

private BackgroundWorker WorkerFactory()
{
    var worker = new BackgroundWorker();
    worker.DoWork += backgroundWorker1_DoWork;
    worker.RunWorkerCompleted += backgroundWorker1_RunWorkerCompleted;

    return worker;
}