Nhibernate多对多关系映射

Question

我对Nhibernate很新。我想通过使用NHibernate作为映射数据库工具在asp.net中开发一个应用程序。

我有以下表模式：

CREATE TABLE [dbo].[tblTeam](
    [TeamID] [int] IDENTITY(1,1) NOT NULL, 
    [TeamName] [varchar](100) NOT NULL 
) 


CREATE TABLE [dbo].[tblEmployee](
    [EmployeeID] [int] IDENTITY(1,1) NOT NULL, 
    [EmployeeName] [varchar](100) NOT NULL 
) 

CREATE TABLE [dbo].[tblTeamEmployee](
    [TeamID] [int] NOT NULL, 
    [EmployeeID] [int] NOT NULL 
) 

这里是我做了NHibernate的映射文件：

<?xml version="1.0" encoding="utf-8" ?> 
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> 
    <class name="TelDir.Core.Domain.Team, TelDir.Core" table="tblTeam" lazy="false"> 
    <id name="ID" column="TeamID" unsaved-value="0"> 
     <generator class="identity" /> 
    </id> 

    <property name="TeamName" column="TeamName" /> 

    <bag name="Employees" cascade="none" table="tblTeamEmployee" lazy="false" access="readonly"> 
     <key column="EmployeeID"/> 
     <many-to-many class="TelDir.Core.Domain.Employee, TelDir.Core" column="TeamID"/> 
    </bag> 

    </class> 
</hibernate-mapping> 


<?xml version="1.0" encoding="utf-8" ?> 
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> 
    <class name="TelDir.Core.Domain.Employee, TelDir.Core" table="tblEmployee" lazy="false"> 
    <id name="ID" column="EmployeeID" unsaved-value="0"> 
     <generator class="identity" /> 
    </id> 

    <property name="EmployeeName" column="EmployeeName" />   

    <bag name="Teams" cascade="none" table="tblTeamEmployee" lazy="false" > 
     <key column="EmployeeID"/> 
     <many-to-many class="TelDir.Core.Domain.Team, TelDir.Core" column="EmployeeID"/> 
    </bag> 

    </class> 
</hibernate-mapping> 

我的POCO类的定义如下：

namespace TelDir.Core.Domain 
{ 
    public class Team { 

     private string _TeamName = ""; 
     private IList<Employee> _employees = new List<Employee>(); 

     public Team() { } 

     public string TeamName { 
      get { return _TeamName } 
      set { _TeamName = value; } 
     } 


     public IList<Employee> Employees 
     { 
      get { return new List<Employee>(_employees).AsReadOnly(); } 
      protected set { _employees = value; }   
     } 

     public void AddEmployee(Employee em) 
     { 
      if (!_employees.Contains(em)){ 
       _employees.Add(em); 
      } 
     } 

     public void RemoveEmployee(Employee em) 
     { 
      if (_employees.Contains(em)){ 
       _employees.Remove(em); 
      } 
     } 
    } 
} 




namespace TelDir.Core.Domain 
{ 
    public class Employee { 

     private string _EmployeeName = ""; 
     private IList<Team> _teams = new List<Team>(); 

     public Employee() { } 

     public string EmployeeName { 
      get { return _EmployeeName} 
      set { _EmployeeName = value; } 
     } 


     public IList<Team> Teams 
     { 
      get { return new List<Team>(_teams).AsReadOnly(); } 
      protected set { _teams = value; }   
     } 

     public void AddTeam(Team tm) 
     { 
      if (!_teams.Contains(tm)){ 
       _teams.Add(tm); 
      } 
     } 

     public void RemoveTeam(Team tm) 
     { 
      if (_teams.Contains(tm)){ 
       _teams.Remove(tm); 
      } 
     } 
    } 
} 

我不确定我的映射和实体类是否定义良好？

假设我有我的表

tblTeam 
     TeamID  |  TeamName 
     -------------------------- 
      1  |   A 
     -------------------------- 
      2  |   B 

tblEmployee 
     EmployeeID |  EmployeeName 
     ------------------------------ 
      1  |  Jhon 
     ------------------------------ 
      2  |  Michel 
     ------------------------------ 
      3  |  Lino 

tblTeamEmployee 
     TeamID  |  EmployeeID 
     ------------------------------ 
      1  |  1 
     ------------------------------ 
      1  |  2 
     ------------------------------ 
      2  |  3 
     ------------------------------ 
      2  |  1   

以下数据如何从团队=“B”在ASP.NET页面中删除员工姓名=“约翰”？

Answer 1

正如你想改变你的收藏，从它删除.AsReadOnly()。

然后，如果你有两个（1和2）的ID，只是做：

var teamB = session.Get<Team>(2); 
teamB.Employees.Remove(teamB); 
session.Flush();