winfrom实现DataGridView全选

  private void CheckDatabasexuan()
        {
            DataGridViewCheckBoxColumn newcol = new DataGridViewCheckBoxColumn();
            newcol.HeaderText = "选择";
            dgvdataBase.Columns.Add(newcol);
        }

 private void ckall_CheckedChanged(object sender, EventArgs e)
        {
            if (ckall.Checked)
            {
                for (int i = 0; i < dgvdataBase.Rows.Count; i++)
                {
                    dgvdataBase.Rows[i].Cells[0].Value = true;
                }
            }
            else
            {
                for (int i = 0; i < dgvdataBase.Rows.Count; i++)
                {
                    dgvdataBase.Rows[i].Cells[0].Value = false;
                }
            }
        }