datagridview 显示行号、插入多行、删除、插入、清空行

private void dgv_BBQ_RowStateChanged( object sender, DataGridViewRowStateChangedEventArgs e)         {             e.Row.HeaderCell.Value = string .Format( "{0}" , e.Row.Index + 1);         }         private void 删除行ToolStripMenuItem_Click( object sender, EventArgs e)         {             dgv_BBQ.Rows.Remove(dgv_BBQ.SelectedRows[0]);             dgv_BBQ.Refresh();         }         private void 清空ToolStripMenuItem_Click( object sender, EventArgs e)         {             dgv_BBQ.Rows.Clear();             dgv_BBQ.Refresh();         }         private void 插入行ToolStripMenuItem_Click( object sender, EventArgs e)         {             dgv_BBQ.Rows.Insert(dgv_BBQ.CurrentRow.Index, "" );             dgv_BBQ.Refresh();         }