禁止點擊header 排序

http://stackoverflow.com/questions/3965304/disable-sorting-when-clicking-datagridview-column-header

http://stackoverflow.com/questions/4334983/best-way-to-disable-the-column-header-sorting-in-datagridview

http://stackoverflow.com/questions/4502442/how-to-disable-sort-in-datagridview

dgDataGridView1.Columns[0].SortMode = DataGridViewColumnSortMode.NotSortable;

或者：

 foreach (var column in dataGridView.Columns)
        {
            column.SortMode = sortMode;
        }