Question

我有两个课程：Transaction和PosReference。

每个transaction可能与posReference相关联
每个posReference必须有transaction

代码：

public class Transaction : Entity 
{
    [Key]
    public Int64 Id { get; set; }
    public virtual PosReference PosReference { get; set; }
}

public class PosReference : Entity 
{
    public Int64 Id { get; set; }
    public virtual Transaction Transaction { get; set; }
    public PosReference(Transaction transaction){
         Id = transaction.Id;
    }
}

和映射编写如下：

modelBuilder.Entity<Transaction>()     // one-to-one or zero relation
         .HasOptional(m => m.PosReference)
         .WithRequired(t => t.Transaction);

如果我尝试一次添加一个transaction和posReference对，然后将上下文保存在数据库中，一切正常。

但是如果我尝试添加多个transaction-posReference对，则抛出此异常：

违反了多重性约束。角色＆＃39; Transaction_PosReference_Target＆＃39;关系＆＃39; Data.Models.Transaction_PosReference＆＃39;具有多重性1或0..1。

是否可以添加多个（一对零/一对）？我应该如何更改我的模型或映射来实现这一目标？

编辑：

两项服务的简化代码如下：

public class TransactionServices {
    private readonly IRepositoryAsync<Transaction> _repository;
    public TransactionServices(IRepositoryAsync<Transaction> repository){
        _repository = repository;
    }
    public Transaction Add(){
        var transaction = new Transaction();
        _repository.Insert(transaction);
        return transaction;
    }
}
public class PosReferenceServices {
    private readonly IRepositoryAsync<PosReference> _repository;
    public PosReferenceServices(IRepositoryAsync<PosReference> repository){
        _repository = repository;
    }
    public PosReference Add(Transaction transaction){
        var posReference = new PosReference(Transaction transaction){
            Transaction = transaction
        };
        _repository.Insert(posReference);
        return posReference;
    }
}

在UnityConfig中配置存储库对象，如下所示：

.RegisterType<IRepositoryAsync<Transaction>, Repository<Transaction>>()
.RegisterType<IRepositoryAsync<PosReference>, Repository<PosReference>>()

以下是添加对象的功能：

public async Task<HttpResponseMessage> AddTransactions(List<PosTransaction> newTransactionList){
    foreach (var posTransactionInfo in newTransactionList){
        // I have omitted some unrelated parameters from PosReference to make code cleaner and to the point
        var transaction = _transactionServices.Add();
        var posReference = _posReferenceServices.Add(transaction);
        // other posReference params would be set according to data in posTransactionInfo 
    }
    await _unitOfWorkAsync.SaveChangesAsync();
    return Request.CreateResponse(Message.PaywandOk());
}

编辑2：两个实体上的Insert函数执行以下操作：

private readonly IDataContextAsync _context;
private readonly DbSet<TEntity> _dbSet;
private readonly IUnitOfWorkAsync _unitOfWork;

public virtual void Insert(TEntity entity)
{
    entity.ObjectState = ObjectState.Added;
    _dbSet.Attach(entity);
    _context.SyncObjectState(entity);         
}

使用一对零/一个关系添加多个对象实体框架

0 个答案: