我如何实现独特键的解决方案?

时间:2011-10-09 22:12:57

标签: c# repository-pattern

我有3张桌子:

Player => PlayerId (Primary Key), Name, etc  
Team => TeamId (Primary Key), Name, etc  
PlayerTeam => PlayerId, TeamId (The combination must be unique)  

然后我有以下内容:

public interface IEntityKey<TKey>
{
    TKey Id { get; }    
}

public interface IRepository<TKey, TEntity> where TEntity : class, IEntityKey<TKey>
{
  IQueryable<TEntity> All();
  TEntity FindBy(Expression<Func<TEntity, bool>> expression);
  ....
  TEntity FindBy(TKey id);
}

现在,虽然上述内容适用于具有单个键的表(例如播放器或团队表),但我如何为我的playerteam表实现它?我需要的是一个满足任意数量的键的解决方案。我更喜欢像......这样的解决方案。

public interface IEntityKey<TKey> where TKey : System.Tuple
{
    TKey Id { get; }    
}

结束

public interface IEntityKey<TKey1, TKey2>
{
    TKey1 Id1 { get; }    
    TKey2 Id2 { get; }    
}

1 个答案:

答案 0 :(得分:1)

只需使用原始IEntityKey界面,TupleTKey

public class PlayerTeam : IEntityKey<Tuple<int, int>>
{
    Tuple<int, int> IEntityKey<Tuple<int, int>>.Id
    {
        get { return Tuple.Create(PlayerId, TeamId); }
    }

    public int PlayerId { get; set; }
    public int TeamId { get; set; }
}

作为旁注,在我看来,PlayerTeam不是一个实体,而只是一个联想......