Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
   System.EventArgs) Handles Button1.Click
        myWebClient.DownloadFileAsync(New Uri("http://Dateiname"), a_filename)
    End Sub
    Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) _
      Handles Button2.Click
        myWebClient.DownloadFileAsync(New Uri("http://Dateiname"), b_filename)
    End Sub
    Private Sub myWebClient_DownloadProgressChanged(ByVal sender As Object, _
      ByVal e As System.Net.DownloadProgressChangedEventArgs) Handles _
      myWebClient.DownloadProgressChanged
        ProgressBar1.Value = e.ProgressPercentage
    End Sub
    Private Sub DownloadFileCompleted(ByVal sender As Object, ByVal e As _
      System.ComponentModel.AsyncCompletedEventArgs) Handles _
      myWebClient.DownloadFileCompleted
        myWebClient.Dispose()
    End Sub