Active Record学习笔记（一）：初步接触
最近开始接触Castle ActiveRecord，学习资料大部分是从网上找到的。这里要特别感谢TerryLee的系列文章：Castle 开发系列 ，在Castle的学习之路上，这个系列文章对我的影响是十分巨大的！除了这个系列文章之外，Castle的官方网站也是学习Castle的好去处！
本篇学习笔记从一个简单对象的CURD操作入手，介绍ActiveRecord！
主要内容：
１．ActiveRecord概述
２．准备数据表
３．编写实体类
４．编写配置文件
５．对象的CRUD操作
６．表示层调用
一、ActiveRecrod概述
ActiveRecord是Castle中提供的一个数据访问框架，它在底层封装了NHibernate的操作。与NHibernate相比，ActiveRecord使用特性来代替映射文件hbm.xml，它提供的简洁的O/R映射会让你惊叹原来实现持久化数据层是那么简单。
二、准备数据表
Create Table [Users]( [ID] Int Identity(1,1) Primary Key, [LoginName] Varchar(50) not null, [Password] Varchar(20) not null)三、编写实体类User
１．引用Castle.ActiveRecord.dll组件；
２．引用Castle.ActiveRecord名称空间：
using Castle.ActiveRecord;３．让User类继承ActiveRecordBase类（此类处于Castle.ActiveRecord名称空间之下）：
public class User : ActiveRecord
{
//
}４．用[ActiveRecrod()]为类添加特性，指出User类对应的数据表是Users：
[ActiveRecord("Users")]public class User : ActiveRecordBase{ //}５．用[Property()]为属性添加特性，指出属性对应数据表中的列：
[ActiveRecord("Users")]public class User : ActiveRecordBase{ private int _id; private string _name; private string _password; //[PrimaryKey]特性指定Id作为主键 //用PrimaryKeyType.Identity来说明了主键的类型为自增型的 [PrimaryKey(PrimaryKeyType.Identity, "ID")] public int Id
{
get { return _id; } set { _id = value; }
} [Property("LoginName")] public string Name { get { return _name; } set { _name = value; } } //若属性名与列名一致可省略不写 [Property] public string Password { get { return _password; } set { _password = value; } }}四、编写配置文件App.config或web.config。由于ActiveRecord在底层封装了NHibernate，故配置文件的信息和NHibernate一致。
App.config：
<?xml version="1.0" encoding="utf-8" ?><configuration> <configSections> <section name="activerecord" type="Castle.ActiveRecord.Framework.Config.ActiveRecordSectionHandler, Castle.ActiveRecord" /> </configSections> <activerecord> <config> <add key="hibernate.connection.driver_class" value="NHibernate.Driver.SqlClientDriver" /> <add key="hibernate.dialect" value="NHibernate.Dialect.MsSql2000Dialect" /> <add key="hibernate.connection.provider" value="NHibernate.Connection.DriverConnectionProvider" /> <add key="hibernate.connection.connection_string" value="UID=sa;Password=123456789;Initial Catalog=Castle;Data Source=EMMALEE" /> </config> </activerecord></configuration><?xml version="1.0"?><configuration> <configSections> <section name="activerecord" type="Castle.ActiveRecord.Framework.Config.ActiveRecordSectionHandler, Castle.ActiveRecord"/> </configSections> <activerecord isWeb="true"> <config> <add key="hibernate.connection.driver_class" value="NHibernate.Driver.SqlClientDriver" /> <add key="hibernate.dialect" value="NHibernate.Dialect.MsSql2000Dialect" /> <add key="hibernate.connection.provider" value="NHibernate.Connection.DriverConnectionProvider" /> <add key="hibernate.connection.connection_string" value="UID=sa;Password=123456789;Initial Catalog=Castle;Data Source=EMMALEE" /> </config> </activerecord> <system.web> <compilation debug="true"/> <authentication mode="Windows"/> <customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm"> <error statusCode="403" redirect="NoAccess.htm" /> <error statusCode="404" redirect="FileNotFound.htm" /> </customErrors> </system.web></configuration>五、对象的CRUD操作。类ActiveRecordBas中定义了许多静态方法用于对象的CRUD操作，如：Create、Delete、DeleteAll、FindAll、FindAllByProperty、FindByPrimaryKey、Save等等一些静态方法。
１．Create操作
User objUser = new User();objUser.Name = "jailu";objUser.Password = "123456789";objUser.Create();２．Read操作
User objUser = User.Find(1); //检索主键ＩＤ为1的User对象string strName = objUser.Name;string strPassword = objUser.Password;３．Update操作
User objUser = User.Find(1); //检索主键ＩＤ为1的User对象objUser.Name = "EmmaLee";objUser.Password = "987654321";objUser.Update();４．Delete操作
User objUser = User.Find(1); //检索主键ＩＤ为1的User对象objUser.Delete();５．完整的User类代码：
using System;using System.Collections.Generic;using System.Text;using System.Collections;using Castle.ActiveRecord;using Castle.ActiveRecord.Queries;namespace CastleTest{ //为User类添加特性，其实就是告诉ActiveRecord，User类所对应的数据库中的数据表名为Users [ActiveRecord("Users")] public class User : ActiveRecordBase { private int _id; private string _name; private string _password; //[PrimaryKey]特性指定Id作为主键 //用PrimaryKeyType.Identity来说明了主键的类型为自增型的 [PrimaryKey(PrimaryKeyType.Identity, "ID")] public int Id { get { return _id; } set { _id = value; } } [Property("LoginName")] public string Name { get { return _name; } set { _name = value; } } //若属性名与列名一致可省略不写 [Property] public string Password { get { return _password; } set { _password = value; } } public static void DeleteAll() { DeleteAll(typeof(User)); } public static IList FindAll() { return (IList)FindAll(typeof(User)); } public static User Find(int id) { return (User)FindByPrimaryKey(typeof(User), id); } /// <summary> /// 根据LogonName查询User对象，在测试HQL查询时用到 /// </summary> /// <param name="LogonName">登录名</param> /// <returns>User对象数组</returns> public static User[] GetUsersByLogonName(string LogonName) { SimpleQuery query = new SimpleQuery(typeof(User),@"from User user where user.Name = ?",LogonName); return (User[])ExecuteQuery(query); } }}六、表示层调用：
private void button1_Click(object sender, EventArgs e){ //初始化，获取连接字符串等信息 IConfigurationSource source = System.Configuration.ConfigurationSettings.GetConfig("activerecord") as IConfigurationSource; ActiveRecordStarter.Initialize(source, typeof(User)); User objUser = new User(); objUser.Name = "jailu"; objUser.Password = "123456789"; objUser.Create();}至此，ActiveRecord的初步接触就算是完成了。
