Question

如何在没有外键和列名不同的旧数据库上创建HasMany关系？我知道如何使用References在HeaderVersion上创建一对一关系，但不知道如何从Header 1创建HasMany到* HeaderVersion。加入条件应该是：

Header.Id1 = HeaderVersion.PId1 AND Header.Id2 = HeaderVersion.PId2

Model http://i41.tinypic.com/30xbfo5.png

域：

public class Header {
    public virtual int Id1 { get; set; }
    public virtual int Id2 { get; set; }
    public virtual string Something { get; set; }
}

public class HeaderVersion {
    public virtual int PId1 { get; set; }
    public virtual int PId2 { get; set; }
    public virtual int Version { get; set; }
    public virtual string SomethingFoo { get; set; }
}

地图：

 public HeaderMap() {
        Table("Header");
        LazyLoad();
        CompositeId().KeyProperty(x => x.Id1, "Id1")
                     .KeyProperty(x => x.Id2, "Id2");
        Map(x => x.Something).Column("Something");
 }

 public HeaderVersionMap() {
        Table("HeaderVersion");
        LazyLoad();
        CompositeId().KeyProperty(x => x.PId1, "PId1")
                     .KeyProperty(x => x.PId2, "PId2")
                     .KeyProperty(x => x.Version, "Version");
        Map(x => x.SomethingFoo).Column("SomethingFoo");
 }

Answer 1

假设Header是（GetHashCode和Equals的省略覆盖）

public class Header
{
    public virtual int Id1 { get; set; }
    public virtual int Id2 { get; set; }
    public virtual string Something { get; set; }
    public virtual ICollection<HeaderVersion> Versions { get; set; }
}

HeaderMap应如下所示：

public class HeaderMap : ClassMap<Header>
{
    public HeaderMap()
    {
        Table("Header");
        LazyLoad();
        CompositeId().KeyProperty(x => x.Id1, "Id1")
                     .KeyProperty(x => x.Id2, "Id2");
        Map(x => x.Something).Column("Something");
        HasMany(x => x.Versions).AsBag().KeyColumns.Add("PId1", "PId2");
        // Fetch, Inverse, Cascade depend on your mapping strategy
    }
}

流畅的NHibernate - HasMany复合键

1 个答案: