Winform中的dataGridView天加自动编号

   private void dataGridView1_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
2         {
3             //自动编号，与数据无关
4              Rectangle rectangle = new Rectangle(e.RowBounds.Location.X, e.RowBounds.Location.Y, dataGridView1.RowHeadersWidth - 4, e.RowBounds.Height);
5             TextRenderer.DrawText(e.Graphics, (e.RowIndex + 1).ToString(), dataGridView1.RowHeadersDefaultCellStyle.Font, rectangle, dataGridView1.RowHeadersDefaultCellStyle.ForeColor, TextFormatFlags.VerticalCenter | TextFormatFlags.Right);
6         }