NHibernate学习第一天（数据的写入 Insert）

转自：http://www.cnblogs.com/mack/archive/2004/09/01/38636.aspx

曾经了解过Hibernate, 印象很深,是个很不错得O/R Mapping FW. 在http://nhibernate.sourceforge.net/上有个从Java移植过来得.NET版本--NHibernate(以下称NH),不过目前还处于PreAlpha Build 2阶段.

出于兴趣以及学习.NET得目的, 花了两天仅看了很小一部分代码:一来源代码注释并不丰富,二来对于Hibernate/NHibernate的使用也很不熟悉,三来有些知识点还不熟悉.

准备工作如下:
1. NHibernate
2. NUnit
3. NHibernate配置文件 monitoring.dll.config 如下:

 

xml version="1.0" encoding="utf-8" ?>
< configuration >
  < configSections >
    < section name ="nhibernate" type = "System.Configuration.NameValueSectionHandler,System,Version=1.0.3300.0,Culture=neutral, PublicKeyToken=b77a5c561934e089" />
  configSections >
  < nhibernate >
    < add key ="hibernate.show_sql" value ="false" />
    < add key ="hibernate.connection.provider" value ="NHibernate.Connection.DriverConnectionProvider" />
    < add key ="hibernate.dialect" value ="NHibernate.Dialect.MsSql2000Dialect" />
    < add key ="hibernate.connection.driver_class" value ="NHibernate.Driver.SqlClientDriver" />
    < add key = "hibernate.connection.connection_string" value ="Server=zephyr;initial catalog= argus;UserID=sa;Password=zephyr;Min Pool Size=2" />
  nhibernate >
configuration >

可以看出以上是一个标准得Config文件,一般由System.Configuration.ConfigurationSettings.GetConfig方法来读取.
蓝色部分才是真正配置NH的地方, 例子中我配置它使用SQL Server, 那些Key/Value的含义很好明白.
值得注意得是,配置文件得文件名很重要,通常对于一个EXE得Assembly来说,是AssemblyName.Config,不过对于Dll Assembly来,对应的配置文件为AssemblyName.dll.config 例如:
MyAssy.exe -> MyAssy.config
MyAssy.dll -> MyAssy.dll.config

我打算在我的monitoring.dll,一个用来监视性能东东中使用NH来持久化数据. 该类库包含了一个TestCase,由NUnit来调用

4.将要被持久化的对象, 即Business Object(BO)

using System;
namespace Argus.Monitoring
{
     public class Monitor
     {
       //dbID & DBID 是NH必须要求的主键
         private int dbID;
         public int  DBID{set{dbID=value;}get{return dbID;}}
         public string MonitorType {get{return "dummy monitor";}}
         public double Value {get{return 12.34;}
         public string Category{get{return "this is category";}}
         public string Name{get{return "this is name";}}
         public string Instance{get{return "this is instance";}}
         public string Computer{get{return "this is computer";}} 
      }
}

这是一个被极度简化的类,省略了Member Method,甚至Property的set方法,因为我打算先试试Insert功能,然后再尝试Load功能

5. 写一个该BO对应的最简单的映射文件

xml version="1.0" encoding="utf-8" ?>
< hibernate-mapping xmlns ="urn:nhibernate-mapping-2.0" >
 
  < class name ="Argus.Monitoring.Monitor,monitoring" table = "record" >
    < id name ="DBID" type ="Int32" >
      < generator class ="identity" />
    id >
   
    < property name ="Computer" type ="String(50)" />
    < property name ="Category" type ="String(50)" />
    < property name ="Name" column ="counter" type ="String(50)" />
    < property name ="Instance" type ="String(50)" />
    
    < property name ="Value" column ="data" type ="Double" />
    < property name ="MonitorType" type ="String(50)" />
  class >
hibernate-mapping >

6. 最后一步 (好累啊~~~), TestCase:
 

using System;

using NUnit.Framework;

using NHibernate;

using Argus.Monitoring;



namespace Test.Monitoring

{

      

     [TestFixture]

     public class MonitoringTest

     {

         [Test] public void NHibernateTest ()

         {

              Argus.Monitoring.Monitor m=new Argus.Monitoring.Monitor ();

              NHibernate.Cfg.Configuration cfg=new NHibernate.Cfg.Configuration ();

              cfg.AddXmlFile ("Argus.Monitoring.Monitor.hbm.xml");

              ISession session= cfg.BuildSessionFactory ().OpenSession();

              session.Save (m);

              session.Close ();

         }

     }

}