Dim sqlcmd As New SqlClient.SqlCommand
                    sqlcmd.Parameters.Clear()
                    sqlcmd.Parameters.Add("@KundenNr", txtKdnr.Text)
                    sqlcmd.Connection = conn
                    sqlcmd.CommandText = "DELETE FROM Kunden WHERE (KundenNr =" & _
                      "@KundenNr)"
                    Try
                        sqlcmd.Connection.Open()
                        sqlcmd.ExecuteNonQuery()
                        sqlcmd.Connection.Close()
                    Catch ex As Exception
                        MsgBox("Fehler: " & ex.ToString)
                        sqlcmd.Connection.Close()
                    End Try