Question

我有一个Nhibernate映射文件，用于简单的用户/角色映射。

以下是映射文件：

Users.hbm.xml

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Sample.Persistence" namespace="Sample.Persistence.Model">
    <class name="User" table="Users">
        <id name="UserKey">
            <generator class="identity"/>
        </id>

        <property name="UserName" column="UserName" type="String" />
        <property name="Password" column="Password" type="Byte[]" />

        <property name="FirstName" column="FirstName" type="String" />
        <property name="LastName" column="LastName" type="String" />
        <property name="Email" column="Email" type="String" />

        <property name="Active" column="Active" type="Boolean" />
        <property name="Locked" column="Locked" type="Boolean" />

        <property name="LoginFailures" column="LoginFailures" type="int" />
        <property name="LockoutDate" column="LockoutDate" type="DateTime" generated="insert" />

        <property name="Expired" column="Expired" type="Boolean" generated="insert"/>

        <set name="Roles" table="UsersRolesBridge"   lazy="false">
            <key column="UserKey" />
            <many-to-many class="Role"
            not-found="exception"
            column="RoleKey" />
        </set>

    </class>
</hibernate-mapping>

Role.hbm.xml

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Sample.Persistence" namespace="Sample.Persistence.Model">
    <class name="Role" table="Roles">
        <id name="RoleKey">
            <generator class="identity"/>
        </id>
        <property name="Name" column="Name" type="String" />

        <set name="Users" inverse="true" table="UsersRolesBridge" lazy="false" >
            <key column="RoleKey" />
            <many-to-many class="User" column="UserKey" />
        </set>
    </class>
</hibernate-mapping>

我能够通过NHibernate为每个用户检索角色，但是当我去保存新对象时，角色不会保存在Bridge表中。

创建并插入用户没有任何问题。我已经检查过，在调用Session.Save（）之前，角色集合（用户的一个字段）正在填充适当的rolekey。

也没有抛出异常。

更新：

添加级联后，仍然没有实际插入M-2-M表。

来自Nhibernate的日志显示如下：

12/22/2010 23:18:11.684 [11] INFO  NHibernate.Engine.Cascade 
Message: processing cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for: Sample.Persistence.Model.User
Exception: 

12/22/2010 23:18:11.686 [11] INFO  NHibernate.Engine.Cascade 
Message: done processing cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for: Sample.Persistence.Model.User
Exception: 

12/22/2010 23:18:11.789 [11] INFO  NHibernate.Engine.Cascade 
Message: processing cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for: Sample.Persistence.Model.User
Exception: 

12/22/2010 23:18:11.792 [11] INFO  NHibernate.Engine.Cascade 
Message: cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for collection: Sample.Persistence.Model.User.Roles
Exception: 

12/22/2010 23:18:11.814 [11] INFO  NHibernate.Engine.Cascade 
Message: done cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for collection: Sample.Persistence.Model.User.Roles
Exception: 

12/22/2010 23:18:11.814 [11] INFO  NHibernate.Engine.Cascade 
Message: done processing cascade NHibernate.Engine.CascadingAction+SaveUpdateCascadingAction for: Sample.Persistence.Model.User

Answer 1

我通常发现许多问题都是由于没有正确设置级联属性引起的。

尝试在Users.hbm.xml文件中设置的角色上设置cascade =“save-update”属性

<set name="Roles" table="UsersRolesBridge"   lazy="false" cascade="save-update">

Answer 2

您尚未在关系中指定级联。默认情况下，插入，更新和删除不是级联的。更多信息：

http://ayende.com/Blog/archive/2006/12/02/nhibernatecascadesthedifferentbetweenallalldeleteorphansandsaveupdate.aspx

NHibernate多对多映射无法正常工作

2 个答案: