public JsonResult ViewCourseStaticByDepartmentId(int?departmentId)
        {
            var courseStatic    = courseManager.GatAllViewCourseStaticManager();
            var getCourseStatic = courseStatic.Where(a => a.DepartmentId == departmentId).ToList();

            return(Json(getCourseStatic, JsonRequestBehavior.AllowGet));
        }