public void Update(User entity)
        {
            var user = _entities.Users.Single(u => u.Id == entity.Id);

            user.Login = entity.Login;
            user.PasswordHash = entity.PasswordHash;

            _entities.SaveChanges();
        }
        public bool IsCorrectUser(User user)
        {
            var isUserExists = _entities.Users.Any(u => u.Login == user.Login && u.PasswordHash == user.PasswordHash);

            return isUserExists;
        }
 public void Delete(User entity)
 {
     _entities.Users.Remove(entity);
     _entities.SaveChanges();
 }
 public bool HasAlready(User user)
 {
     return _entities.Users.Where(u => u.Login == user.Login).ToList().Count >= 1;
 }
 public void Add(User entity)
 {
     _entities.Users.Add(entity);
     _entities.SaveChanges();
 }