Private Sub btnReihung_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles btnReihung.Click
        DataGridView2.SuspendLayout()
        For i As Integer = 0 To DataGridView2.Rows.Count - 1
            DataGridView2.Rows(i).Cells("Sp_2").Value = i
        Next i
        DataGridView2.ResumeLayout()
    End Sub