啥？客户叫在DataGridView的左上角添加CheckBox?

 private void InitColumnInfo()
        {
            int index = 0;

            DataGridViewCheckBoxColumn colCB = new DataGridViewCheckBoxColumn();
            DatagridViewCheckBoxHeaderCell cbHeader = new DatagridViewCheckBoxHeaderCell();
            colCB.HeaderCell = cbHeader;
            colCB.HeaderText = "";
            colCB.FillWeight = 50;
            cbHeader.OnCheckBoxClicked += new CheckBoxClickedHandler(cbHeader_OnCheckBoxClicked);
            dataGridView2.Columns.Insert(index, colCB);

            System.Windows.Forms.DataGridViewCellStyle dataGridViewCellStyle2 = new System.Windows.Forms.DataGridViewCellStyle();
            dataGridViewCellStyle2.Alignment = System.Windows.Forms.DataGridViewContentAlignment.MiddleCenter;//211, 223, 240
            dataGridViewCellStyle2.ForeColor = System.Drawing.Color.Blue;
            dataGridViewCellStyle2.SelectionForeColor = System.Drawing.Color.Blue;
            dataGridView2.Columns[index].DefaultCellStyle = dataGridViewCellStyle2;
        }

private void cbHeader_OnCheckBoxClicked(bool state)
        {
            //这一句很重要结束编辑状态
            dataGridView2.EndEdit();
            dataGridView2.Rows.OfType().ToList().ForEach(t => t.Cells[0].Value = state);
        }