using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;
using System.Reflection;namespace SelfToolsHelper
{public interface Ilog{void CreateLog();}public class EventLog : Ilog{public void CreateLog(){Console.Write("Create EventLog");}}public class TxtLog : Ilog{public void CreateLog(){Console.Write("createTxtLog");}}public class DiskLog : Ilog{public void CreateLog(){Console.Write("Create DiskLog");}}public interface IFactory{Ilog CreateLogFactory();}public class EventFactory : IFactory{public Ilog CreateLogFactory(){return new EventLog();}}public class TexFactory : IFactory{public Ilog CreateLogFactory(){return new TxtLog();}}public class DiskFactory : IFactory{public Ilog CreateLogFactory(){return new DiskLog();}}//思考 要是有1w个 log 那 我要建立两万个class (log and factory) ，多付出1w的工作量。//是否可以优化我的factory方法？public class FactoryNew<T>{public object CreateLogInstance(){return Activator.CreateInstance<T>();}}

public class FactoryTEST{public void TEST(){IFactory factory = new DiskFactory();Ilog log = factory.CreateLogFactory();log.CreateLog();//面向接口抽象，打印出：Create DiskLog
        }public void TestNew(){FactoryNew<EventLog> eventfact =new FactoryNew<EventLog> ();Ilog log = eventfact.CreateLogInstance() as EventLog;log.CreateLog();}public void TestNewSecond(){FactoryNew<DiskLog> diskFactory = new FactoryNew<DiskLog>();Ilog log = diskFactory.CreateLogInstance() as DiskLog;log.CreateLog();}//以上两个方法是在我知道 到底是使用哪种log方法的测试。、//现在我不知道我到底要实例化哪种log 而是读取配置文件 来动态创建 这样该怎么办？

//思路 我应该从配置文件里面知道我到底改实例一个什么泛型的工厂 就是说我应该传递什么类型进入 泛型工厂？// 假如 配置在了config文件中。//1<appSettings>//<add key="logtype" value="EventLog"></add>//</appSettings>public void TestNewThrid(){string strfactoryName = ConfigurationSettings.AppSettings["logtype"];#region 此部分是思考过程object o= Activator.CreateInstance(Assembly.GetCallingAssembly().FullName, strfactoryName);Type t = o.GetType();//得带log type。 然后根据logtype 再声明 facttorynew<T>;object obj =Assembly.Load(Assembly.GetCallingAssembly().FullName).CreateInstance(strfactoryName);//  FactoryNew < typeof(obj) > diskFactory = new FactoryNew< typeof(obj) >(); 走不通。// obj.调用方法。。。。。。。 失败了！//思考，我为什要先创建factory 再创建log?!!! 我的目的是创建Log 。额 log  log已经创建了。。。。// 这里才是真正实现，注意 配置config的时候直接使用 log Type!跳过FactoryIlog logObj = Assembly.Load(Assembly.GetCallingAssembly().FullName).CreateInstance(strfactoryName) as Ilog;logObj.CreateLog();//搞定。//#endregion}
}}

// 参考资料 http://terrylee.cnblogs.com/archive/2006/01/04/310716.html