Which method should I call?
The pro version of grid allows to set custom sorting rules
dhtmlx.com/docs/products/dhtmlxG … _sort.html
so it possible to defined rules for your custom date format as well.
Also, when you are using dhxCalendar or calendar excells it possible to use
grid.setDateFormat
command, which allow to defined custom date format. Sorting for such column with work automatically.