datagridview显示行号

添加datagridview的RowPostPaint事件。

private void dataGridView1_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
        {
            var grid = sender as DataGridView;
            var rowIdx = (e.RowIndex + 1).ToString();

            var centerFormat = new StringFormat()
            {
                // right alignment might actually make more sense for numbers  
                Alignment = StringAlignment.Center,
                LineAlignment = StringAlignment.Center
            };

            var headerBounds = new Rectangle(e.RowBounds.Left, e.RowBounds.Top, grid.RowHeadersWidth, e.RowBounds.Height);
            e.Graphics.DrawString(rowIdx, this.Font, SystemBrushes.ControlText, headerBounds, centerFormat);
        }