public async Task <IActionResult> Index(int id) { var course = await courseService.GetFullCourseByIdAsync(id); var userId = User.FindFirstValue(ClaimTypes.NameIdentifier); if (!string.IsNullOrWhiteSpace(userId)) { ViewBag.IsInShoppingCart = await appCourseListService.IsInListAsync(id, userId, CourseListType.ShoppingCart); ViewBag.IsInWishList = await appCourseListService.IsInListAsync(id, userId, CourseListType.WishList); ViewBag.IsPurchased = await appCourseListService.IsPurchasedAsync(id, userId); } return(View(course)); }