VB.Net下载文件暂停和恢复（没有文件大小下载限制）

Question

我在这里有一个下载文件，并取消了下载代码，但是我想如果有恢复或暂停下载按钮和网络连接处理功能，那么当PC突然失去互联网连接时，程序将自行重试。

这是我的代码

声明书

    'Download Link
    Public DLink As String
    'File Extension
    Public DExt As String
    'File Information
    Public DInfo As String
    'FIle Name
    Public DFName As String

    Dim wc As WebClient

表单加载代码

 wc = New WebClient()

进度条码

    Private Sub ProgChanged(ByVal sender As Object, ByVal e As DownloadProgressChangedEventArgs)
        pbStatus.Value = e.ProgressPercentage
        lblProgPerc.Text = e.ProgressPercentage.ToString() + "%"
        lblln.Text = String.Format("{0} MB's / {1} MB's", (e.BytesReceived / 1024D / 1024D).ToString("0.00"), (e.TotalBytesToReceive / 1024D / 1024D).ToString("0.00"))
        If pbStatus.Value = pbStatus.Maximum Then


            'lblln.ForeColor = Color.Lime

            lblln.Text = ("Download Complete")

            selectdownload.Start()
            DSoftwareDownloadButton.Enabled = True
            BrowseButton.Enabled = True
            DisklessListBox.Enabled = True
            DisklessComboBox.Enabled = True
            'readyvhdlist.Enabled = True

            DSoftwareCancelDownloadButton.Enabled = False
        End If
    End Sub

下载代码

 Private Sub DownloadNow()
        Try
            AddHandler wc.DownloadProgressChanged, AddressOf ProgChanged
            wc.DownloadFileAsync(New Uri(DLink), DownloadLocationBox.Text + "\" + DisklessComboBox.Text + " " + DisklessListBox.Text + DExt)
            lblln.Visible = True
            lblProgPerc.Visible = True


            selectdownload.Stop()
            BrowseButton.Enabled = False
            DSoftwareDownloadButton.Enabled = False
            DisklessComboBox.Enabled = False
            DisklessListBox.Enabled = False

            DSoftwareCancelDownloadButton.Enabled = True

        Catch ex As Exception
            MsgBox(ex.Message, CType(MessageBoxIcon.Error, MsgBoxStyle), MainUI.BrandMsgBox)
            selectdownload.Start()

            BrowseButton.Enabled = True
            DSoftwareDownloadButton.Enabled = True

            DisklessComboBox.Enabled = True
            DisklessListBox.Enabled = True

            DSoftwareCancelDownloadButton.Enabled = False
        End Try


    End Sub

取消下载按钮

    Private Sub DSoftwareCancelDownloadButton_Click(sender As Object, e As EventArgs) Handles DSoftwareCancelDownloadButton.Click
        wc.CancelAsync()
        MsgBox("The User Cancelled The Download", CType(MessageBoxIcon.Information, MsgBoxStyle), MainUI.BrandMsgBox)

        selectdownload.Start()
        DSoftwareDownloadButton.Enabled = True
        BrowseButton.Enabled = True
        DisklessListBox.Enabled = True
        DisklessComboBox.Enabled = True


    End Sub