Sub FillCbx(ByVal dt As DataTable, ByVal cbx As ComboBox)
        Dim vorname As String
        Dim nachname As String
        For Each r As DataRow In dt.Rows
            If r("Vorname").ToString <> "" And r("Nachname").ToString <> _
              "" And r("Vorname").ToString.Length > 2 And r( _
              "Nachname").ToString.Length > 2 Then
                vorname = r("Vorname").ToString.Substring(0, 1)
                nachname = r("Nachname").ToString.Substring(0, 1)
                cbx.Items.Add(vorname + nachname)
            End If
        Next
    End Sub