vb.net2005里 webclient实现文件下载

Private WithEvents myWebclient As WebClient
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim remoteUri As String = "http://office.9zp.com/UploadFile/Word排版艺术.rar"
        Dim fileName As String = "C:/xx.rar"
        myWebclient = New WebClient()
        myWebclient.DownloadFileAsync(New Uri(remoteUri), fileName)

    End Sub
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        myWebclient.CancelAsync()   '中断下载
    End Sub

    Private Sub myWebclient_DownloadFileCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.AsyncCompletedEventArgs) Handles myWebclient.DownloadFileCompleted
        MsgBox("下载完毕")
    End Sub

    Private Sub myWebclient_DownloadProgressChanged(ByVal sender As Object, ByVal e As System.Net.DownloadProgressChangedEventArgs) Handles myWebclient.DownloadProgressChanged
        Me.Label1.Text = CStr(e.UserState) & "    downloaded " & e.BytesReceived & " of " & e.TotalBytesToReceive & " bytes. " & e.ProgressPercentage & " % complete..."

    End Sub