The DXGrid control allows data sorting by multiple columns. Any previous sorting is not cleared when calling the SortBy method.
If the grid's data isn't sorted by the specified column, the SortBy method sorts data by its values in the specified order. The new sort order applies an additional sorting condition to the one previously applied. The grid creates a new GridSortInfo object with the specified settings and inserts it into the SortInfo collection at the position specified by the sortedIndex parameter. If this parameter is negative, or exceeds the index of the last element within the SortInfo collection, the GridSortInfo object is appended to the collection.
End-users are allowed to sort data if the view's DataViewBase.AllowSorting property is set to true.
To learn more, see Sorting in Code and Sorting.