public ActionResult GridData(string orderBy = "ID", bool desc = false)
{
Response.AppendHeader("X-Total-Row-Count", db.TimeSlots.Count(t => t.Event.ID == eventID).ToString());
ObjectQuery<TimeSlot> timeslots = (db as IObjectContextAdapter).ObjectContext.CreateObjectSet<TimeSlot>();
timeslots = timeslots.OrderBy("it." + orderBy + (desc ? " desc" : ""));
return PartialView(timeslots.Where(t => t.Event.ID == eventID));
}