Nhibernate3循序渐进(三): 一对多映射和级联保存

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

namespace NHibernate3.Domain
{
     public  class Department
    {
         public  virtual  int? ID {  get;  set; }

         public  virtual  string Name {  get;  set; }
    }
}

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

< hibernate-mapping  xmlns ="urn:nhibernate-mapping-2.2"  assembly ="NHibernate3.Domain"  namespace ="NHibernate3.Domain" >
   < class  name ="Department"  table ="T_Department"  lazy ="true"   >
     < id  name ="ID"  type ="int"  column ="DepartmentID" >
       < generator  class ="native" />
     </ id >
  
     < property  name ="Name"  type ="string" >
       < column  name ="Name"  length ="50" />
     </ property >

   </ class >
</ hibernate-mapping >

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

namespace NHibernate3.Domain
{
     public  class Student
    {
         public  virtual  int? ID {  get;  set; }

         public  virtual  string Name {  get;  set; }

         public  virtual Department Dept {  get;  set; }
    }
}

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

< hibernate-mapping  xmlns ="urn:nhibernate-mapping-2.2"  assembly ="NHibernate3.Domain"  namespace ="NHibernate3.Domain" >
   < class  name ="Student"  table ="T_Student"  lazy ="true"   >
     < id  name ="ID"  type ="int"  column ="StudentID" >
       < generator  class ="native" />
     </ id >

     < property  name ="Name"  type ="string" >
       < column  name ="Name"  length ="50" />
     </ property >

     < many-to-one  name ="Dept"  column ="DepartmentID"  cascade ="all" />

   </ class >
</ hibernate-mapping >

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

using NHibernate;
using NHibernate.Cfg;
using NHibernate3.Domain;

namespace NHibernate3.DAL
{
     public  class ScSession
    {
         private ISessionFactory sessionFactory;

         public ScSession()
        {
             var cfg =  new NHibernate.Cfg.Configuration().Configure( " Config/hibernate.cfg.xml ");
            sessionFactory = cfg.BuildSessionFactory();
        }

         public  void Save()
        {
             using (ISession session =  this.sessionFactory.OpenSession())
            {
                 var dept =  new Department { Name =  " 计算机系 " };

                 var student1 =  new Student { Name =  " 李四 ", Dept = dept };
                 var student2 =  new Student { Name =  " 张三 ", Dept = dept };

                ITransaction tran = session.BeginTransaction();
                 try
                {
                     // 持久化Department类

                    session.Save(student1);
                    session.Save(student2);

                    tran.Commit();
                }
                 catch (Exception ex)
                {
                    tran.Rollback();
                     throw ex;
                }
            }
        }

         public  void GetAll()
        {
             using (ISession session =  this.sessionFactory.OpenSession())
            {
                 var students = session.CreateQuery( "  from Student ").List<Student>();

                Console.WriteLine();
                Console.WriteLine( " ******* 学生信息 ******* ");
                 foreach (Student student  in students)
                {
                    Console.WriteLine( " 学生：{0} ", student.Name);

                    Console.WriteLine( " 系：{0} ", student.Dept.Name);
                }
            }
        }
    }
}