将外键映射为主键流畅的NHibernate

时间:2014-04-12 13:14:47

标签: c# fluent-nhibernate composite-id

我有以下表格方案:

User
    - Id       (PK)
    - Username 

Advert
    - Id    (PK)
    - Title

AdvertPhoto
    - Advert (PK) (Also a FK for Advert table)
    - Image

Bid
    - Advert (PK) (Also a FK for Advert table)
    - User   (PK) (Also a FK for User table)
    - Value

好的,我正在尝试使用以下代码映射这些实体:

public class AdvertMapping : BaseMapping<Advert> {
    public AdvertMapping() : base("Advert") {
        Id(model => model.Id).Not.Nullable().Unique().GeneratedBy.Identity();
        Map(model => model.Title).Not.Nullable().Length(100).Insert().Update();
    }
}

public class AdvertPhotoMapping : BaseMapping<Advert> {
    public AdvertPhotoMapping() : base("AdvertPhoto") {
        Id(model => model.Advert)
            .Column("Id")
            .GeneratedBy.Foreign("Advert");

        Map(model => model.Description).Nullable();
        Map(model => model.Photo).CustomSqlType("image").Not.Nullable();
        References(model => model.Advert, "Advert").Not.Nullable().Not.LazyLoad();
    }
}

public class BidMapping { //: BaseMapping<Bid> {
    public BidMapping() : base("Bid") {
        Id(model => model.Advert, "Advert").GeneratedBy.Foreign("Advert");
            CompositeId()
                .KeyReference(model => model.Advert, "Advert")
                .KeyReference(model => model.User, "User");

            Map(model => model.Value).Not.Nullable().Insert().Update();
            References(model => model.Advert, "Advert").Not.Nullable().Not.LazyLoad();
    }
}

好的,当Fluent NHibernate试图引用AdvertPhotoMapping类中的Advert列时我得到一个例外,我不知道BidMapping CompositeId是否被正确映射。

我得到的例外是:

{"Could not determine type for: SYB.Engine.Entities.Advert, SYB.Engine, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null, for columns: NHibernate.Mapping.Column(Advert)"}

我做错了什么? 谢谢大家!

1 个答案:

答案 0 :(得分:1)

通常这就是我如何映射一对一的关系:

public class AdvertPhotoMapping : BaseMapping<Advert> {
    public AdvertPhotoMapping() : base("AdvertPhoto") {
        Id(model => model.Advert)
            .Column("Id")
            .GeneratedBy.Foreign("Advert");

        Map(model => model.Description).Nullable();
        Map(model => model.Photo).CustomSqlType("image").Not.Nullable();
        HasOne(model => model.Advert).Constrained();
    }
}

public class AdvertMapping : BaseMapping<Advert> {
    public AdvertMapping() : base("Advert") {
        Id(model => model.Id).Not.Nullable().Unique().GeneratedBy.Identity();
        Map(model => model.Title).Not.Nullable().Length(100).Insert().Update();
        HasOne(x => x.AdvertPhoto).Cascade.All();
    }
}

此外,您不需要BidMapping中的参考映射。它应该是这样的:

CompositeId()
    .KeyReference(model => model.Advert, "Advert")
    .KeyReference(model => model.User, "User");

     Map(model => model.Value).Not.Nullable().Insert().Update();