给定以下类:
using System.Collections.Generic;
namespace FluentMappingsQuestion
{
public class Entity
{
public virtual int Id { get; set; }
public virtual IDictionary<string, Property> Properties { get; set; }
}
public class Property
{
public virtual Entity OwningEntity { get; set; }
public virtual string Name { get; set; }
public virtual int Value { get; set; }
public virtual decimal OtherValue { get; set; }
}
}
我该如何使用NHibernate(最好是流畅的风格)来映射它们,以便能够实现以下操作:
[Test]
public void EntityPropertyMappingTest()
{
using (var session = _factory.OpenSession())
{
var entity = new Entity();
// (#1) I would *really* like to use this
entity.Properties["foo"] = new Property { Value = 42, OtherValue = 42.0M };
session.Save(entity);
session.Flush();
// (#2) I would like the entity below to "update itself"
// on .Save or .Flush. I got it to work with .Load()
Assert.AreEqual(42, entity.Properties["foo"].Value);
Assert.AreEqual(42.0M, entity.Properties["foo"].OtherValue);
Assert.AreEqual("foo", entity.Properties["foo"].Name);
Assert.AreEqual(entity, entity.Properties["foo"].Owner);
}
}
我几乎已经通过以下映射来完成了这个:
// class EntityMap : ClassMap<Entity>
public EntityMap()
{
Id(x => x.Id);
HasMany(x => x.Properties)
.Cascade.AllDeleteOrphan()
.KeyColumn("EntityId")
.AsMap(x => x.Name);
}
// class PropertyMap : ClassMap<Property>
public PropertyMap()
{
Id(x => x.Id);
References(x => x.OwningEntity).Column("EntityId");
Map(x => x.Name).Length(32);
Map(x => x.Value);
{
我所遇到的问题:
- 如果我使用
Entity.Properties
.Inverse()
,会出现错误 - 如果我不使用
.Inverse()
,NHibernate会执行INSERT(Entity), INSERT(Property), UPDATE(Property)
而不是只有INSERT(Entity), INSERT(Property)
- 如果我把
Property.Name
.Not.Nullable()
属性设置为非空,也会出现错误 - 如果我不使用
.Not.Nullable()
,数据库模式中就会有一个空缺