You can use the following code in order to achieve the requirement.You need to write it in the fetch method-
str todayDate;
;
element.printJobSettings().SetTarget(PrintMedium::File);
element.printJobSettings().format(printFormat::PDF);
todaydate = Date2str(SystemDateGet(),213,2,0,2,0,2);
element.printJobSettings().FileName(strfmt('c:\\Report%1.pdf',todaydate));
str todayDate;
;
element.printJobSettings().SetTarget(PrintMedium::File);
element.printJobSettings().format(printFormat::PDF);
todaydate = Date2str(SystemDateGet(),213,2,0,2,0,2);
element.printJobSettings().FileName(strfmt('c:\\Report%1.pdf',todaydate));