VB.NET从BackgroundWorker更改进度条值？

Question

我有2个进度条。现在我在代码中做了一些其他的事情，这需要时间来执行，因此需要使用backgroundworker。我没有太多的想法如何使用backgroundworker。我这里没有包含的其他代码执行得很好，但progressbar的值不会改变，也不会改变它们的文本。我将如何实现这一目标？

Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork 

    Dim LM As RegistryKey = Registry.LocalMachine 
    Dim LM_SW As RegistryKey = LM.OpenSubKey("Software") 
    Dim LM_MS As RegistryKey = LM_SW.OpenSubKey("Microsoft") 
    Dim LM_Win As RegistryKey = LM_MS.OpenSubKey("Windows") 
    Dim LM_CV As RegistryKey = LM_Win.OpenSubKey("CurrentVersion") 
    Dim AppPaths As RegistryKey = LM_CV.OpenSubKey("App Paths") 
    Dim NrOfFiles1 As Integer = AppPaths.SubKeyCount 

    ProgressBar2.Maximum = NrOfFiles1 
    ProgressBar1.Maximum = 100 

    For Each FormatString As String In AppPaths.GetSubKeyNames() 
     ProgressBar2.Value += 1/NrOfFiles1 
     ProgressBar1.Value += 1 * ProgressBar2.Value/100/10 
     ProgressBar1.Text = ProgressBar1.Value & "%" 
     ProgressBar2.Text = ProgressBar2.Value & "%" 
    Next 

    ProgressBar2.Value = 0 

End Sub 

Answer 1

使用Backgroundworker的ProgressChanged事件。 在你的DoWork方法，调用

BackgroundWorker1.ReportProgress(Percentage) 

凡百分比是一个整数值

然后在ProgressChanged事件，你可以操纵你的进度条。

Private Sub backgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As DoWorkEventArgs) Handles backgroundWorker1.DoWork 

    Dim worker As BackgroundWorker = CType(sender, BackgroundWorker) 

    '''YOUR OTHER CODE 
    worker.ReportProgress(PERCENTAGE) 
    '''YOUR OTHER CODE 

    End Sub 

    ' This event handler updates the progress. 
    Private Sub backgroundWorker1_ProgressChanged(ByVal sender As System.Object,   ByVal e As ProgressChangedEventArgs) Handles backgroundWorker1.ProgressChanged 
     ProgressBar1.Text = e.ProgressPercentage.ToString() & "%" 
     ProgressBar1.Value = e.ProgressPercentage 
    End Sub