ASP.NETCore-如何將用戶模型中自動生成的ID插入到商家模型中

我在 ASP.NET Core 中有這些模型：

public abstract class EntityBase
{
    [Key]
    public int Id { get; set; }
}

public class User : EntityBase
{
    public string Username { get; set; }
    public string Password { get; set; }
    public virtual ICollection<Merchant> Merchants { get; set; }
}

public class Merchant : EntityBase
{
    public string MerchantName { get; set; }
    public string AccountNumber { get; set; }
    public int? UserId { get; set; }

    [ForeignKey("UserId")]
    public virtual User User { get; set; }
    public virtual ICollection<Mandate> Mandates { get; set; }
}

視圖模型（DTO）：

public class RegisterDto
{
    public string MerchantName { get; set; }

    [Required(ErrorMessage = "Account Number is required")]
    [MaxLength(50)]
    public string AccountNumber { get; set; }

    [MaxLength(100)]
    [Required(ErrorMessage = "Username is required")]
    [RegularExpression(@"^\S*$", ErrorMessage = "No white space allowed")]
    public string Username { get; set; }

    [MaxLength(128)]
    [Required(ErrorMessage = "Password is required")]
    public string Password { get; set; }
}

物體映射器：

public class EntityMapper
{
    public User FromRegisterDtoToUser(RegisterDto register)
    {
        User user = new User()
        {
            Username = register.Username,
            Password = register.Password,
        };
        return user;
    }

    public Merchant FromRegisterDtoToMerchant(RegisterDto register)
    {
        Merchant merchant = new Merchant()
        {
            MerchantName = register.MerchantName,
            AccountNumber = register.AccountNumber,
            UserId        = ?  
        };
          return merchant;
    }
}

身份驗證服務：

    public async Task<UserDto> register(RegisterDto register)
    {
        var userExists = await _unitOfWork.UserRepository.GetByUsername(register.Username);

        if (userExists != null)
        {
            throw new Exception("User already exists!");
        }
        else
        {
            try
            {
                register.Password = User.ComputeSha256Hash(register.Password);

                var mapper = new EntityMapper();
                var user = mapper.FromRegisterDtoToUser(register);
                var merchant = mapper.FromRegisterDtoToMerchant(register);

                await _unitOfWork.UserRepository.Insert(user);
                await _unitOfWork.MerchantRepository.Insert(merchant);
                await _unitOfWork.SaveChangesAsync();

                if (user != null)
                {
                    var token = GetToken(user);
                    var map = new EntityMapper();
                    return map.FromUserToUserDto(user, token);
                }

                return null;
            }
            catch (Exception e)
            {
                throw new Exception(e.Message);
            }
        }
    }

Merchant 中的 UserId 是 User 中 Id 的外鍵。Id 是自動生成的。

由于用戶和商家資料是同時插入的，我想自動插入 UserId 作為從 User 生成的 Id 在：

        Merchant merchant = new Merchant()
        {
            MerchantName = register.MerchantName,
            AccountNumber = register.AccountNumber,
            UserId        = ...?  
        };

我如何實作這一目標？

謝謝

uj5u.com熱心網友回復：

我不確定您使用的是什么資料庫技術/框架（我假設是物體框架）但是如果UserId是在資料庫插入時生成的，您將需要在插入用戶后保存對資料庫的更改，并在插入時再次執行商人。基本上

  await _unitOfWork.UserRepository.Insert(user);
  await _unitOfWork.SaveChangesAsync(); // user should have an id now.
  merchant.UserId = user.Id;
  await _unitOfWork.MerchantRepository.Insert(merchant);
  await _unitOfWork.SaveChangesAsync();

標籤：C＃ asp.net核心

上一篇：反序列化沒有屬性名稱的復雜JSON回應

下一篇：AmbiguousMatchException：請求匹配多個端點。火柴？