DataGridView 显示行数

private void dataGridView_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
        {
            try
            {
                DataGridView dgv = sender as DataGridView;
                Rectangle rectangle = new Rectangle(e.RowBounds.Location.X,
                                                    e.RowBounds.Location.Y,
                                                    dgv.RowHeadersWidth - 4,
                                                    e.RowBounds.Height);


                TextRenderer.DrawText(e.Graphics, (e.RowIndex + 1).ToString(),
                                        dgv.RowHeadersDefaultCellStyle.Font,
                                        rectangle,
                                        dgv.RowHeadersDefaultCellStyle.ForeColor,
                                        TextFormatFlags.VerticalCenter | TextFormatFlags.Right);
            }
            catch (Exception ex)
            {

            }
        }