public static string saveTimeCells(int userId, List <String> timecells, string startDate, string endDate)
{
ScheduleBLL bll = new ScheduleBLL();
bll.userId = userId;
bll.update(timecells, Util.StringToDate(startDate) ?? DateTime.MaxValue, Util.StringToDate(endDate) ?? DateTime.MinValue);
return("Successfully saved");
}