NHibernate映射多对多关系

Question

我无法映射多对多关系！我有一个Users表，Roles表和UserRoles表。用户可以有许多角色。角色表只存储像Admin，Editor等角色的名称。Userroles表存储用户与角色的关系。

当我保存用户时，会保存用户信息，但不保存角色信息。

这里是我的映射：

 <?xml version="1.0"?> 
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" 
auto-import="true" assembly="EStudy.Business" namespace="EStudy.Business.Entities"> 
    <class name="EStudy.Business.Entities.User, EStudy.Business" lazy="false" table="Users"> 
    <id name="Id" access="property" column="UserId"> 
     <generator class="native" /> 
    </id> 

    <property name="UserName" access="property" column="UserName" /> 
    <property name="Password" access="property" column="Password" /> 
    <property name="FirstName" access="property" column="FirstName"/> 
    <property name="LastName" access="property" column="LastName"/> 
    <property name="DateCreated" access="property" column="DateCreated" generated="insert" type="datetime" /> 
    <property name="DateModified" access="property" generated="always" column="DateModified" type="datetime" /> 


    <bag name="Roles" table="UserRoles" cascade="all" lazy="true" access="nosetter.camelcase-underscore" > 
     <key column="UserId"/> 
     <many-to-many class="Role" column="RoleId" /> 
    </bag> 
    </class> 





</hibernate-mapping> 


     <?xml version="1.0" encoding="utf-8" ?> 

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" 
auto-import="true" assembly="EStudy.Business" namespace="EStudy.Business.Entities"> 
    <class name="EStudy.Business.Entities.Role, EStudy.Business" lazy="false" table="Roles"> 
    <id name="Id" access="property" column="RoleId"> 
     <generator class="native" /> 
    </id> 

    <property name="RoleName" access="property" column="RoleName"/> 

    <bag name="Users" table="UserRoles" access="nosetter.camelcase-underscore" cascade="all" inverse="true"> 
     <key column="RoleId"/> 
     <many-to-many class="EStudy.Business.Entities.User, EStudy.Business" column="UserId"/> 
    </bag> 
    </class> 

</hibernate-mapping> 
    using System; 
    using System.Collections.Generic; 
    using System.Collections.ObjectModel; 
    using System.Linq; 
    using System.Text; 

    namespace EStudy.Business.Entities 
    { 
     public class User 
     { 
      public User() { } 

      public void AddRole(RoleType roleType) 
      { 
       AddRole(new Role() { RoleName = roleType.ToString() }); 
      } 

      private IList<Role> _roles = new List<Role>(); 

      public virtual int Id { get; set; } 
      public virtual string UserName { get; set; } 
      public virtual string Password { get; set; } 
      public virtual string FirstName { get; set; } 
      public virtual string LastName { get; set; } 
      public virtual DateTime DateCreated { get; set; } 
      public virtual DateTime DateModified { get; set; } 


      public virtual IList<Role> Roles 
      { 
       get { return new ReadOnlyCollection<Role>(_roles); } 
      } 

      protected virtual void AddRole(Role role) 
      { 
       _roles.Add(role); 
       role.AddUser(this); 

      } 
     } 
    } 

    using System; 
    using System.Collections.Generic; 
    using System.Collections.ObjectModel; 
    using System.Linq; 
    using System.Text; 


    namespace EStudy.Business.Entities 
    { 
     public class Teacher : User 
     { 
      public Teacher() 
      { 

      } 
     } 

    } 

    using System; 
using System.Collections.Generic; 
using System.Collections.ObjectModel; 
using System.Linq; 
using System.Text; 

namespace EStudy.Business.Entities 
{ 
    public enum RoleType 
    { 
     Teacher, 
     Student, 
     Admin 
    } ; 

    public class Role 
    { 
     private IList<User> _users = new List<User>(); 

     public virtual int Id { get; set; } 
     public virtual string RoleName { get; set; } 
     public virtual RoleType RoleType { get; set;} 

     public void AddUser(User user) 
     { 
      _users.Add(user); 
     } 

     public virtual IList<User> Users 
     { 
      get { return _users; } 
     } 

    } 

} 

上述映射文件名为User.hbm.xml，它包含了用户和角色及其与UserRole的表关系的映射。

Answer 1

解决方案是在事务中进行插入。

Answer 2

您错过了cascade =“all-delete-orphan”。检查NH文档。