public IActionResult OnGet()
        {
            var usersId = HttpContext.Session.GetInt32("users_id");

            if (usersId == null)
            {
                if (HttpContext.Request.Cookies.ContainsKey("users_id"))
                {
                    usersId = int.Parse(HttpContext.Request.Cookies["users_id"]);
                    var usersName = HttpContext.Request.Cookies["users_name"];
                    HttpContext.Session.SetInt32("users_id", (int)usersId);
                    HttpContext.Session.SetString("users_name", usersName);
                }
                else
                {
                    return(Redirect("SignIn"));
                }
            }
            var usersDao = new UsersDao();

            Users   = usersDao.GetById((int)usersId);
            Courses = usersDao.GetCourses((int)usersId);
            var purchaseDao = new PurchaseDao();

            Purchases = purchaseDao.GetByUsersId((int)usersId);
            foreach (var purchase in Purchases)
            {
                purchase.CourseName = Courses.First(c => c.Id == purchase.CourseId).Name;
            }
            return(null);
        }