How would I implement a solution for unique keys?
I have 3 tables:
Player => PlayerId (Primary Key), Name, etc
Team => TeamId (Primary Key), Name, etc
PlayerTeam => PlayerId, TeamId (The combination must be unique)
then I have the following:
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);
}
Now while the above would work fine for tables with a single key such as the player or team table, how would I implement it for my playerteam table? What I need is a solution that would cater for any number of keys. I would prefer a solution such as ...
public interface IEntityKey<TKey> where TKey : System.Tuple
{
TKey Id { get; } 开发者_运维知识库
}
over
public interface IEntityKey<TKey1, TKey2>
{
TKey1 Id1 { get; }
TKey2 Id2 { get; }
}
Just use your original IEntityKey
interface, with a Tuple
as TKey
:
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; }
}
As a side note, it seems to me that PlayerTeam
is not an entity but merely an association...
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