public ActionResult AddCourse()
{
List <CategoryVM> categories = courseBll.getAllCategories();
SelectList categsList = new SelectList(categories, "category_id", "category_name");
ViewBag.categsList = categsList;
List <servicesVM> services = serviceBll.getAllServices();
SelectList servicesList = new SelectList(services, "service_id", "service_name");
ViewBag.servicesList = servicesList;
List <instructorVM> instructors = InstructorBll.getAllIstructors();
SelectList instructorsList = new SelectList(instructors, "instructor_id", "instructor_name");
ViewBag.instructorsList = instructorsList;
return(PartialView());
}