public async Task <IActionResult> AboutUser(string userId, int kursId)
        {
            if (userId != null && kursId != 0)
            {
                var have = await db.UserKurs.FirstOrDefaultAsync(x => x.UserId == userId && x.KursId == kursId);

                if (have != null)
                {
                    db.Remove(have);
                    await db.SaveChangesAsync();
                }
                else
                {
                    UserKurs uk = new UserKurs {
                        UserId = userId, KursId = kursId
                    };

                    await db.AddAsync(uk);

                    await db.SaveChangesAsync();
                }
                AboutUserView auv = new AboutUserView()
                {
                    User     = db.Users.FirstOrDefault(x => x.Id == userId),
                    Kurs     = await db.Kurs.ToListAsync(),
                    UserKurs = await db.UserKurs.Where(x => x.UserId == userId).ToListAsync()
                };
                return(View(auv));
            }

            return(RedirectToAction("UserList"));
        }
        public async Task <IActionResult> AboutUser(string id)
        {
            AboutUserView auv = new AboutUserView()
            {
                User     = db.Users.FirstOrDefault(x => x.Id == id),
                Kurs     = await db.Kurs.ToListAsync(),
                UserKurs = await db.UserKurs.Where(x => x.UserId == id).ToListAsync()
            };

            return(View(auv));
        }