NHibernate双向多对多关联

Question

我有一个有以下描述的课程:

public class Customer {
    public ISet<Client> Contacts { get; protected set;}
}

我想将Contacts属性映射到下表:

CREATE TABLE user_contacts (
    user1 uuid NOT NULL,
    user2 uuid NOT NULL
)

我希望它双向映射,即当Customer1添加到Customer2的Contacts时,Customer1的Contacts集合应包含Customer2(可能仅在实体重新加载后).我怎么能这样做？

更新当然我可以映射从左到右和从右到左的集合,然后在运行时进行组合,但它会......嗯......不讨厌......还有其他解决方案吗？无论如何,非常感谢你,FryHard!

Answer 1

看一下这个链接，了解 hibernate 所谓的单向多对多关联。在Castle ActiveRecord中，我使用 HasAndBelongsToMany 链接，但我不确定它在 nhibernate 中的映射方式到底如何。

尽管更深入地研究您的问题，但看起来您将从 customer 到 user_contacts 进行双向链接，这可能会破坏多对多链接。我将举一个例子，看看我能想出什么。

从 ActiveRecord 导出 hbm 文件显示了这一点

<?xml version="1.0" encoding="utf-16"?>
<hibernate-mapping  auto-import="true" default-lazy="false" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:nhibernate-mapping-2.2">
  <class name="NHibernateMapping.Customer, NHibernateMapping" table="Customer" schema="dbo">
    <id name="Id" access="property" column="Id" type="Int32" unsaved-value="0">
      <generator class="identity">
      </generator>
    </id>
    <property name="LastName" access="property" type="String">
      <column name="LastName" not-null="true"/>
    </property>
    <bag name="ChildContacts" access="property" table="user_contacts" lazy="false">
      <key column="user1" />
      <many-to-many class="NHibernateMapping.Customer, NHibernateMapping" column="user2"/>
    </bag>
    <bag name="ParentContacts" access="property" table="user_contacts" lazy="false" inverse="true">
      <key column="user2" />
      <many-to-many class="NHibernateMapping.Customer, NHibernateMapping" column="user1"/>
    </bag>
  </class>
</hibernate-mapping>

活动记录示例：

[ActiveRecord("Customer", Schema = "dbo")]
public class Customer
{
    [PrimaryKey(PrimaryKeyType.Identity, "Id", ColumnType = "Int32")]
    public virtual int Id { get; set; }

    [Property("LastName", ColumnType = "String", NotNull = true)]
    public virtual string LastName { get; set; }

    [HasAndBelongsToMany(typeof(Customer), Table = "user_contacts", ColumnKey = "user1", ColumnRef = "user2")]
    public IList<Customer> ChildContacts { get; set; }

    [HasAndBelongsToMany(typeof(Customer), Table = "user_contacts", ColumnKey = "user2", ColumnRef = "user1", Inverse = true)]
    public IList<Customer> ParentContacts { get; set; }
}

希望能帮助到你！