Question

我有这段代码：

Private Sub KickoffExtract()
    actionStatus.Text = "Se instaleaza actualizarea.. va rugam asteptati."
    lblProgress.Text = "Se extrage..."
    Dim args(2) As String
    args(0) = GetSettingItem("./updUrl.info", "UPDATE_FILENAME")
    args(1) = extractPath
    _backgroundWorker1 = New System.ComponentModel.BackgroundWorker()
    _backgroundWorker1.WorkerSupportsCancellation = False
    _backgroundWorker1.WorkerReportsProgress = False
    AddHandler Me._backgroundWorker1.DoWork, New DoWorkEventHandler(AddressOf Me.UnzipFile)
    _backgroundWorker1.RunWorkerAsync(args)
End Sub

Private Sub UnzipFile(ByVal sender As Object, ByVal e As DoWorkEventArgs)
    Dim extractCancelled As Boolean = False
    Dim args() As String = e.Argument
    Dim zipToRead As String = args(0)
    Dim extractDir As String = args(1)
    Try
        Using zip As ZipFile = ZipFile.Read(zipToRead)
            totalEntriesToProcess = zip.Entries.Count
            SetProgressBarMax(zip.Entries.Count)
            AddHandler zip.ExtractProgress, New EventHandler(Of ExtractProgressEventArgs)(AddressOf Me.zip_ExtractProgress)
            zip.ExtractAll(extractDir, Ionic.Zip.ExtractExistingFileAction.OverwriteSilently)
        End Using
    Catch ex1 As Exception
        MessageBox.Show(String.Format("Actualizatorul a intampinat o problema in extragerea pachetului.  {0}", ex1.Message), "Error Extracting", MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1)
    End Try
End Sub

Private Sub SetProgressBarMax(ByVal n As Integer)
    If ProgBar.InvokeRequired Then
        ProgBar.Invoke(New Action(Of Integer)(AddressOf SetProgressBarMax), New Object() {n})
    Else
        ProgBar.Value = 0
        ProgBar.Maximum = n
        ProgBar.Step = 1
    End If
End Sub

Private Sub zip_ExtractProgress(ByVal sender As Object, ByVal e As ExtractProgressEventArgs)
    If _operationCanceled Then
        e.Cancel = True
        Return
    End If

    If (e.EventType = Ionic.Zip.ZipProgressEventType.Extracting_AfterExtractEntry) Then
        StepEntryProgress(e)
    ElseIf (e.EventType = ZipProgressEventType.Extracting_BeforeExtractAll) Then
    End If
End Sub

Private Sub StepEntryProgress(ByVal e As ExtractProgressEventArgs)
    If ProgBar.InvokeRequired Then
        ProgBar.Invoke(New ZipProgress(AddressOf StepEntryProgress), New Object() {e})
    Else
        ProgBar.PerformStep()
        System.Threading.Thread.Sleep(100)
        nFilesCompleted = nFilesCompleted + 1
        lblProgress.Text = String.Format("{0} din {1} fisiere...({2})", nFilesCompleted, totalEntriesToProcess, e.CurrentEntry.FileName)
        Me.Update()
    End If
End Sub

和按钮上的代码：

If Not File.Exists("./" + GetSettingItem("./updUrl.info", "UPDATE_FILENAME")) Then
    MessageBox.Show("Actualizarea nu s-a descarcat corespunzator.", "Nu se poate extrage", MessageBoxButtons.OK)
End If

If Not String.IsNullOrEmpty("./" + GetSettingItem("./updUrl.info", "UPDATE_FILENAME")) And
   Not String.IsNullOrEmpty(extractPath) Then
    If Not Directory.Exists(extractPath) Then
        Directory.CreateDirectory(extractPath)
    End If
    nFilesCompleted = 0
    _operationCanceled = False
    btnUnzip.Enabled = False
    KickoffExtract()
End If

完成UnZip流程后如何显示消息？我试过了

If ProgBar.Maximum Then
    MsgBox("finish")
End If

但它不起作用。我正在使用dotnetzip 1.9，大部分代码来自UnZip示例。

Answer 1

如果您查看BackgroundWorker的文档，您会发现有两个事件可以链接到代码中的事件处理程序。
其中一个是RunWorkerCompleted，在他们说的MSDN页面中

在后台操作完成后发生，已取消，或者提出了例外。

因此，编写事件处理程序并绑定事件只是一个问题。

AddHandler Me._backgroundWorker1.RunWorkerCompleted, New RunWorkerCompletedEventHandler(AddressOf Me.UnzipComplete)

然后

Private Sub UnzipComplete(ByVal sender As System.Object, _
                          ByVal e As RunWorkerCompletedEventArgs) 
    If e.Cancelled = True Then
        MessageBox.Show("Canceled!")
    ElseIf e.Error IsNot Nothing Then
        MessageBox.Show("Error: " & e.Error.Message)
    Else
        MessageBox.Show("Unzip Completed!")
    End If
End Sub

如何在完成解压缩过程后显示MsgBox

1 个答案: