Dim a As New ArrayList
    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button5.Click
' FÜLLEN
        Dim r As New Random(Now.Second)
        Me.ListBox2.BeginUpdate()
        While r.Next(0, 1000) <> 0
            a.Add(r.Next)
        End While
        Me.ListBox2.DataSource = a
        Me.ListBox2.EndUpdate()
    End Sub
    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button6.Click
' EINTRAG ENTFERNEN
        a.RemoveAt(0)
        a.RemoveAt(1)
        Me.ListBox2.DataSource = Nothing
        Me.ListBox2.BeginUpdate()
        Me.ListBox2.DataSource = a
        Me.ListBox2.EndUpdate()
    End Sub