NHibernate 入门

（纯属学习记录）

https://www.hibernate.org/343.html 上下载个NHibernate release：2.0.1GA  

然后参照 Nhibernat quick start guide(https://www.hibernate.org/362.html)

不做全盘翻译 只把基本步骤和碰到的错误记录

Here are the steps we are going to perform:

• Create the table to persist the .NET class to.(在数据库建表)
• Create a .NET class that needs to be persisted.(生成表对应的持久类)
• Create a mapping file so NHibernate knows how to persist the .NET class' properties(生成隐射XML文件)
• Create a configuration file for NHibernate to know how to connect to your database（在web.config里建立数据库连接等配置）
• Use the NHibernate API(用NHibernate类操作数据)

1.建表 SQL如下

use NHibernate
go

CREATE TABLE users (
  LogonID nvarchar(20) NOT NULL default '0',
  Name nvarchar(40) default NULL,
  Password nvarchar(20) default NULL,
  EmailAddress nvarchar(40) default NULL,
  LastLogon datetime default NULL,
  PRIMARY KEY  (LogonID)
)
go

2.新建C#类库文件 命名NHibernate.Examples

using System;

namespace NHibernate.Examples.QuickStart
{
    public class User
    {
        private string id;
        private string userName;
        private string password;
        private string emailAddress;
        private DateTime lastLogon;


        public User()
        {
        }

        public string Id 
        {
            get { return id; }
            set { id = value; }
        }

        public string UserName 
        {
            get { return userName; }
            set { userName = value; }
        }

        public string Password 
        {
            get { return password; }
            set { password = value; }
        }

        public string EmailAddress 
        {
            get { return emailAddress; }
            set { emailAddress = value; }
        }

        public DateTime LastLogon 
        {
            get { return lastLogon; }
            set { lastLogon = value; }
        }
        
    }
}

3.映射xml文件(User.xml)

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">
    <class name="NHibernate.Examples.QuickStart.User, NHibernate.Examples" table="users">
        <id name="Id" column="LogonId" type="String" length="20"> 
            <generator class="assigned" /> 
        </id> 
        <property name="UserName" column="Name" type="String" length="40"/> 
        <property name="Password" type="String" length="20"/> 
        <property name="EmailAddress" type="String" length="40"/>
        <property name="LastLogon" type="DateTime"/>
    </class>
</hibernate-mapping>

(注意：可以用其他的方法去配置哪个CLASS对应哪个映射XML，这里用最简单的方法，在类的同项目下建个同名的 xml)

 4.配置数据库连接（在webconfig里面配置）

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section
      name="nhibernate" 
      type="System.Configuration.NameValueSectionHandler, System, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" 
    />
  </configSections>

  <nhibernate>
    <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=localhost;initial catalog=nhibernate;Integrated Security=SSPI"
    />
  </nhibernate>
</configuration>

 5.调用NHibernate类进行插入操作（引用下载Nhibernate里面的Nhibernate.dll,log4net.dll,Iesi.Collections.dll）

using NHibernate.Cfg;
using NHibernate;

            //The Configuration object has knowledge of all the mappings 
            //   that are going on between .NET classes and the backend database. 
            NHibernate.Cfg.Configuration cfg = new NHibernate.Cfg.Configuration();

            //The Configuration object will look through the assembly for any files ending in .hbm.xml.
            //There are other ways to add the mapping files, but this is probably the easiest.
            //The other way is to mapping the CLASS and the mapping xml in the web config  
            cfg.AddAssembly("NHibernate.Examples");

            ISessionFactory factory = cfg.BuildSessionFactory();
            ISession session = factory.OpenSession();
            ITransaction transaction = session.BeginTransaction();

            NHibernate.Examples.QuickStart.User user = new NHibernate.Examples.QuickStart.User();
            user.Id = "2";
            user.LastLogon = DateTime.Now;
            user.Password = "123456";
            user.UserName = "T-Mac";
            user.EmailAddress = "t_mac@nba.com";

            // Tell NHibernate that this object should be saved
            session.Save(user);

            // commit all of the changes to the DB and close the ISession
            transaction.Commit();
            session.Close();

 以上步骤是对的,但是会报Could not find the dialect in the configuration这个错误，这是数据库配置问题 ，

因为这个教程版本是1....的，所以要更改一些东西1.

1.映射xml文件(User.xml) 里面

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">

 换成

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">

 2.数据库配置要改（我用的是sqlserver2005）

<configSections>
        <section name="hibernate-configuration" type="NHibernate.Cfg.ConfigurationSectionHandler,NHibernate"/>
    </configSections>
    <hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
        <session-factory>
            <property name="connection.provider">
        NHibernate.Connection.DriverConnectionProvider
      </property>
            <property name="dialect">
        NHibernate.Dialect.MsSql2005Dialect
      </property>
            <property name="connection.driver_class">
        NHibernate.Driver.SqlClientDriver
      </property>
            <property name="connection.connection_string">
        Data Source=AA\BL;Integrated Security=True; initial catalog=NHibernate
      </property>
      <property name="proxyfactory.factory_class">
        NHibernate.ByteCode.LinFu.ProxyFactoryFactory, NHibernate.ByteCode.LinFu
      </property>

    </session-factory>
    </hibernate-configuration>

  这样运行会报另外一个错The ProxyFactoryFactory was not configured. 因为没有引用上面那个配置中的工厂类

所以在引用下  Required_For_LazyLoading文件夹下的 LinFu下的NHibernate.ByteCode.LinFu.dll

当然也可以用 Castle 那要改下配置

基本上可以运行成功了~

 哦 忘了 要把类里面的那些字段前面全部加上 virtual 修饰符