DataGridView显示行号

用DataGridView的RowPostPaint事件在RowHeaderCell中绘制行号：

 

private void dataGridView1_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
{
    if (dataGridView1.Rows.Count < 1000) //RowHeaderWidth
       dataGridView1.RowHeadersWidth = 30;
    if (dataGridView1.Rows.Count>=1000 && dataGridView1.Rows.Count<9999)
       dataGridView1.RowHeadersWidth = 43;
    if (dataGridView1.Rows.Count >= 9999)
       dataGridView1.RowHeadersWidth = 46;

   
    try
    {
         SolidBrush v_sb = new SolidBrush(dataGridView1.RowHeadersDefaultCellStyle.ForeColor);
         int v_lineno = 0;
         v_lineno = e.RowIndex + 1;
         string v_line = v_lineno.ToString();
         e.Graphics.DrawString(v_line, e.InheritedRowStyle.Font, v_sb, e.RowBounds.Location.X + 6, e.RowBounds.Location.Y + 5);
     }

     catch (Exception ex)
     {
           MessageBox.Show("a"+ex.Message,"Error");
     }
}