Sorting Datawindow

Here's a script to sort datawindow rows when the column header is clicked as in windows explorer.
Requirements : Column header should be same as column name and ended with '_t'. For Example, Column Name : 'emp_id'
Column Header : 'emp_id_t'
Condition : Only one column can sort at a time.

String ls_old_sort, ls_column
Char lc_sort
/* Check whether the user clicks on the column header */
IF Right(dwo.Name,2) = '_t' THEN
    ls_column = LEFT(dwo.Name, LEN(String(dwo.Name)) - 2)
    /* Get old sort, if any. */
    ls_old_sort = dw_1.Describe("Datawindow.Table.sort")
    /* Check whether previously sorted column and currently clicked column are same or not. If     both are same then check for the sort order of previously sorted column (A - Asc, D - Des) and     change it. If both are not same then simply sort it by Ascending order. */
    IF ls_column = LEFT(ls_old_sort, LEN(ls_old_sort) - 2) THEN
         lc_sort = RIGHT(ls_old_sort, 1)
        IF lc_sort = 'A' THEN
             lc_sort = 'D'
        ELSE
             lc_sort = 'A'
        END IF
        dw_1.SetSort(ls_column+" "+lc_sort)
    ELSE
        dw_1.SetSort(ls_column+" A")
    END IF
    dw_1.Sort()
END IF