asp.net-mvc - 添加到数据库的重复用户

Question

我尝试向我的数据库中添加一个新值。 UserPassword 和 RePassword 必须具有相同的值，并且数据库中必须不存在具有 UserName 的用户。

  public User NewUser(int HotelID, string UserName, string UserPassword, string RePassword, string FullName, string Email, bool Active, bool MasterUser)
    {
        User user = new User();
        user.HotelID = HotelID;
        user.UserName = UserName;
        user.UserPassword = UserPassword;
        user.FullName = FullName;
        user.Email = Email;
        user.IsActiveq = Active;
        user.IsMaster = MasterUser;

        var cekUser = (from c in _UserRepository.All()
                       where c.HotelID == HotelID
                       select c.UserName).ToList();
        if (UserPassword == RePassword)
        {
            foreach (string cek in cekUser)
            {
                var x = cek;
                if (UserName != x)
                {
                    _UserRepository.Add(user);
                }
            }
        }

        _UserRepository.CommitChanges();

        return user;

    }

每次我运行我的代码时，都会向数据库中添加一个新行，尽管数据库中已经存在具有所提供用户名的用户。

为什么会这样？我的代码的哪一部分是错误的？

Answer 1

我认为你的代码应该是这样的:

if (UserPassword == RePassword)
{
    // Also I thinks you should finish whether user existed logic in database
    // but for now, let's follow your original logic
    var existedUsers = (from c in _UserRepository.All()
                       where c.HotelID == HotelID
                       select c.UserName).ToList();

    if (!existedUsers.Any(u => u == UserName))
    {
        _UserRepository.Add(user);
        _UserRepository.CommitChanges();
    }   
}