private void dgvChannel_CellClick(object sender, DataGridViewCellEventArgs e)         {             if (e.ColumnIndex == -1 || e.RowIndex == -1) return;             int x = dgvChannel.CurrentCell.ColumnIndex;//获取鼠标的点击列             if (x == 0)//点击第一列是单选。             {                 for (int i = 0; i < dgvChannel.Rows.Count; i++)                 {                     DataGridViewCheckBoxCell checkcell = (DataGridViewCheckBoxCell)dgvChannel.Rows[i].Cells[0];                     checkcell.Value = false;                 }                 DataGridViewCheckBoxCell ifcheck = (DataGridViewCheckBoxCell)dgvChannel.Rows[e.RowIndex].Cells[0];                 ifcheck.Value = true;             }         }