在Fluent NHibernate中映射复合键

pan*_*ang 40 fluent-nhibernate

我是流利的NHibernate的新手.现在我遇到映射复合键的一个问题.任何人都可以指出URL或样品吗?

Jam*_*ory 50

有一种CompositeId方法.

public class EntityMap : ClassMap<Entity>
{
  public EntityMap()
  {
      CompositeId()
      .KeyProperty(x => x.Something)
      .KeyReference(x => x.SomethingElse);
  }
}
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  • 请注意,在新版本的NHibernate中,UseCompositeId被CompositeId替换,WithKeyProperty只是KeyProperty. (17认同)
  • 在这种情况下,KeyProperty和KeyReference有什么区别? (5认同)
  • 我看到的例子表明KeyProperty将是"ID",KeyReference将是实体.因此,将KeyProperty用于"CustomerID",将KeyReference用于"Customer"实例 (5认同)
  • @Rob Walker:WithReferenceProperty也成了KeyReference (2认同)

小智 5

如果这是你的第一堂课

public class EntityMap : ClassMap<Entity>
{
  public EntityMap()
  {
    UseCompositeId()
      .WithKeyProperty(x => x.Something)
      .WithReferenceProperty(x => x.SomethingElse);
  }
}
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这是第二个参考实体

public class SecondEntityMap : ClassMap<SecondEntity>
    {
      public SecondEntityMap()
      {
        Id(x => x.Id);

        ....

        References<Entity>(x => x.EntityProperty)
          .WithColumns("Something", "SomethingElse")
          .LazyLoad()
          .Cascade.None()
          .NotFound.Ignore()
          .FetchType.Join();

      }
    }
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小智 5

另一件要注意的事情是,您必须使用 CompositeId 覆盖实体的 Equals 和 GetHashCode 方法。鉴于接受的答案映射文件,您的实体将如下所示。

public class Entity
{
   public virtual int Something {get; set;}
   public virtual AnotherEntity SomethingElse {get; set;}


   public override bool Equals(object obj)
    {
        var other = obj as Entity;

        if (ReferenceEquals(null, other)) return false;
        if (ReferenceEquals(this, other)) return true;
        return other.SomethingElse == SomethingElse && other.Something == Something;
    }

    public override int GetHashCode()
    {
        unchecked
        {
            return (SomethingElse.GetHashCode()*397) ^ Something;
        }
    }

}
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