代码：

private void dataGridView1_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)        {            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);        }

效果：