樂在其中設(shè)計模式

介紹保證一個類僅有一個實例，并提供一個訪問它的全局訪問點。示例保證一個類僅有一個實例。Single1011^^tenericClass-屬性雪Instance:T-■套類型ISingletonCreatar[AClass-字段二，inst：±tlch:T泛型實現(xiàn)單例模式SingletonusingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Singleton日田{白中///<summary>I///泛型實現(xiàn)單例模式///</summary>卜///<typeparamname="T">需要實現(xiàn)單例的類</typeparam>publicclassSingleton<T>whereT:new()攤{斡///<summary>I///返回類的實例///</summary>publicstaticTInstance白中{H申get{returnSingletonCreator.instance;}}IclassSingletonCreator攤{internalstaticreadonlyTinstance=newT();b}TestusingSystem;usingSystem.Data;usingSystem.Configuration;usingSystem.Collections;usingSystem.Web;usingSystem.Web.Security;usingSystem.Web.UI;usingSystem.Web.UI.WebControls;usingSystem.Web.UI.WebControls.WebParts;usingSystem.Web.UI.HtmlControls;usingPattern.Singleton;publicpartialclassSingleton:System.Web.UI.Page曰田{protectedvoidPage_Load(objectsender,EventArgse)白中{//使用單例模式，保證一個類僅有一個實例Response.Write(Singleton<Test>.Instance.Time);Response.Write("<br/>");IResponse.Write(Singleton<Test>.Instance.Time);Response.Write("<br/>");I//不用單例模式I Testt=newTest();I Response.Write(t.Time);Response.Write("<br/>");I Testt2=newTest();I Response.Write(t2.Time);Response.Write("<br/>");}}publicclassTest曰田{privateDateTime_time;IIpublicTest()白中{ISystem.Threading.Thread.Sleep(3000);_time=DateTime.Now;}publicstringTime由由{get{return_time.ToString();}}}運行結(jié)果2007-2-1022:35:112007-2-1022:35:112007-2-1022:35:142007-2-1022:35:17樂在其中設(shè)計模式(C#)-適配器模式(AdapterPattern)介紹將一個類的接口轉(zhuǎn)換成客戶希望的另外一個接口。Adapter模式使得原本由于接口不兼容而不能一起工作的那些類可以一起工作。示例有一個Message實體類，某個類對它的操作有Insert()和Get()方法?，F(xiàn)在需要把這個類轉(zhuǎn)到另一個接口，分別對應(yīng)Add()和Select()方法。

MessageModelusingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Adapter曰田｛攤///<summary>I///Message實體類///</summary>publicclassMessageModel攤{斡///<summary>I ///構(gòu)造函數(shù)///</summary>I ///<paramname="msg">Message內(nèi)容</param>///<paramname="pt">Message發(fā)布時間</param>publicMessageModel(stringmsg,DateTimept)白中{this._message=msg;this._publishTime=pt;}privatestring_message;白中///<summary>///Message內(nèi)容///</summary>publicstringMessage白中{get{return_message;}set{_message=value;}}privateDateTime_publishTime;白中///<summary>I ///Message發(fā)布時間///</summary>publicDateTimePublishTime白中{get{return_publishTime;}set{_publishTime=value;}}}}SqlMessageusingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Adapter曰田{攤///<summary>I///源(Adaptee)角色I///Sql方式操作Message///</summary>publicclassSqlMessage白中{R申///<summary>I///獲取Message///</summary>///<returns></returns>publicList<MessageModel>Get()白中{List<MessageModel>l=newList<MessageModel>();l.Add(newMessageModel("SQL方式獲取Message",DateTime.Now));IIreturnl;}攤///<summary>///插入Message///</summary>I///<paramname="mm">Message實體對象</param>///<returns></returns>publicboolInsert(MessageModelmm)攤{〃代碼略Ireturntrue;}}}IMessageusingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Adapter日田{白中///<summary>I///目標(Target)角色I///操作Message的接口卜///</summary>IpublicinterfaceIMessage{斡///<summary>I ///獲取Message///</summary>卜 ///<returns></returns>I List<MessageModel>Select();I白中///<summary>I /// 插入MessageI /// </summary>I /// <paramname="mm">Message實體對象</param>卜 /// <returns></returns>I boolAdd(MessageModelmm);}}MessageusingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Adapter曰田{攤///<summary>I///適配器(Adapter)角色I ///類適配器I ///把源適配到這個類///</summary>publicclassMessage:SqlMessage,IMessage攤{斡///<summary>I///獲取Message///</summary>///<returns></returns>publicList<MessageModel>Select()百中{returnbase.Get();}攤///<summary>///插入Message///</summary>I///<paramname="mm">Message實體對象</param>///<returns></returns>publicboolAdd(MessageModelmm)攤{returnbase.Insert(mm);}}}Message?usingSystem;usingSystem.Collections.Generic;usingSystem.Text;namespacePattern.Adapter曰田{攤///<summary>I///適配器(Adapter)角色I///對象適配器I///把源適配到這個類///</summary>publicclassMessage?:IMessage攤{privateSqlMessage_sqlMessage;白中///<summary>I///構(gòu)造函數(shù)///</summary>publicMessage2()白中{_sqlMessage=newSqlMessage();}白中///<summary>I///獲取Message///</summary>///<returns></returns>publicList<MessageModel>Select()百中{return_sqlMessage.Get();}攤///<summary>///插入Message///</summary>I///<paramname="mm">Message實體對象</param>///<returns></returns>publicboolAdd(MessageModelmm)攤{return_sqlMessage.Insert(mm);}}}clientusingSystem;usingSystem.Data;usingSystem.Configuration;usingSystem.Collections;usingSystem.Web;usingSystem.Web.Security;usingSystem.Web.UI;usingSystem.Web.UI.WebControls;usingSystem.Web.UI.WebControls.WebParts;usingSystem.Web.UI.HtmlControls;usingPattern.Adapter;publicpartialclassAdapter:System.Web.UI.Page曰田{protectedvoidPage_Load(objectsender,EventArgse)白中{IMessagem;I m=newMessage();I Response.Write("類適配器方式<br/>");I Response.Write(m.Add(newMessageModel("插入"，DateTime.Now)));Response.Write("<br/>");I Response.Write(m.Select()[0].Message + " " + m.Select()[0].PublishTime.ToString());Response.Write("<br/><br/>");II m=newMessage2();I Response.Write("對象適配器方式<br/>");I Respo