Question

使用BackgroundWorker Class我需要运行一个从数据库中提取数据的进程，并在没有进度条的标签上以完成百分比的形式报告进度。

我在这种方法中看到的大多数示例都使用了ProgressChanged Event中的循环，这使得该过程重复：

例如：调用如下所示的代码会导致多次调用DB，从而重复查询。

Private Sub backgroundWorker1_DoWork(ByVal sender As System.Object, _

ByVal e As DoWorkEventArgs) Handles backgroundWorker1.DoWork
    Dim worker As BackgroundWorker = CType(sender, BackgroundWorker)
    Dim i As Integer

    For i = 1 To 10
        If (worker.CancellationPending = True) Then
            e.Cancel = True
            Exit For
        Else
            ' This method is rightfully called multiple times.
            GetDbDataHere()
            worker.ReportProgress(i * 10)
        End If
    Next
End Sub

此处报告更新：

Private Sub backgroundWorker1_ProgressChanged(ByVal sender As System.Object, _
ByVal e As ProgressChangedEventArgs) Handles
 backgroundWorker1.ProgressChanged
    resultLabel.Text = (e.ProgressPercentage.ToString() + "%")
End Sub

如果没有进度条，如何运行流程并显示已完成的百分比，但多次调用BackgroundWorker正在处理的方法？

如何在没有进度条的标签上仅使用百分比报告后台工作人员进度

0 个答案: