public ActionResult Onchage_RoomType(string RoomTypeID)
 {
     if (RoomTypeID != null)
     {
         //Lay danh sach phong theo hạng phòng
         ViewData["Room"] = new SelectList(data.Getview_GetRoomForRoomType(RoomTypeID), "ID", "Name");
     }
     return(View());
 }