原型模式(Prototype Pattern)

介绍

用原型实例指定创建对象的种类，并且通过拷贝这个原型来创建新的对象。

示例

有一个Message实体类，现在要克隆它。

　　MessageModel

using System;using System.Collections.Generic;using System.Text;namespace Pattern.Prototype{    /// 
    /// Message实体类    /// 
    public class MessageModel    {        /// 
        /// 构造函数        /// 
        /// Message内容        /// Message发布时间        public MessageModel(string msg, DateTime pt)        {            this._message = msg;            this._publishTime = pt;        }        private string _message;        /// 
        /// Message内容        /// 
        public string Message        {            get { return _message; }            set { _message = value; }        }        private DateTime _publishTime;        /// 
        /// Message发布时间        /// 
        public DateTime PublishTime        {            get { return _publishTime; }            set { _publishTime = value; }        }    }}

　　ShallowCopy

using System;using System.Collections.Generic;using System.Text;namespace Pattern.Prototype{    /// 
    /// 浅拷贝    /// 
    public class ShallowCopy : ICloneable    {        /// 
        /// 构造函数        /// 
        public ShallowCopy()        {                    }        /// 
        /// 实现ICloneable的Clone()方法        /// 
        /// 
             public Object Clone()        {            return this.MemberwiseClone();        }        private MessageModel _mm;        /// 
        /// Message实体对象        /// 
        public MessageModel MessageModel        {            get { return _mm; }            set { _mm = value; }        }    }}

　　DeepCopy

using System;using System.Collections.Generic;using System.Text;namespace Pattern.Prototype{    /// 
    /// 深拷贝    /// 
    public class DeepCopy : ICloneable    {        /// 
        /// 构造函数        /// 
        public DeepCopy()        {                    }        /// 
        /// 构造函数        /// 
        /// Message实体对象        public DeepCopy(MessageModel mm)        {            _mm = mm;        }        /// 
        /// 实现ICloneable的Clone()方法        /// 
        /// 
             public Object Clone()        {            return new DeepCopy(new MessageModel(_mm.Message, _mm.PublishTime));        }        private MessageModel _mm;        /// 
        /// Message实体对象        /// 
        public MessageModel MessageModel        {            get { return _mm; }            set { _mm = value; }        }    }}

　　Client

using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using Pattern.Prototype;public partial class Prototype : System.Web.UI.Page{    protected void Page_Load(object sender, EventArgs e)    {        Response.Write("ShallowCopy演示如下：
");        ShowShallowCopy();        Response.Write("DeepCopy演示如下：
");        ShowDeepCopy();        }    private void ShowShallowCopy()    {        ShallowCopy sc = new ShallowCopy();        sc.MessageModel = new MessageModel("ShallowCopy", DateTime.Now);        ShallowCopy sc2 = (ShallowCopy)sc.Clone();        Response.Write(sc.MessageModel.Message);        Response.Write("
");        Response.Write(sc2.MessageModel.Message);        Response.Write("
");        sc.MessageModel.Message = "ShallowCopyShallowCopy";        Response.Write(sc.MessageModel.Message);        Response.Write("
");        Response.Write(sc2.MessageModel.Message);        Response.Write("
");    }    private void ShowDeepCopy()    {        DeepCopy sc = new DeepCopy();        sc.MessageModel = new MessageModel("DeepCopy", DateTime.Now);        DeepCopy sc2 = (DeepCopy)sc.Clone();        Response.Write(sc.MessageModel.Message);        Response.Write("
");        Response.Write(sc2.MessageModel.Message);        Response.Write("
");        sc.MessageModel.Message = "DeepCopyDeepCopy";        Response.Write(sc.MessageModel.Message);        Response.Write("
");        Response.Write(sc2.MessageModel.Message);        Response.Write("
");    }}

　　运行结果

　　ShallowCopy演示如下：

　　ShallowCopy

　　ShallowCopy

　　ShallowCopyShallowCopy

　　ShallowCopyShallowCopy

　　DeepCopy演示如下：

　　DeepCopy

　　DeepCopy

　　DeepCopyDeepCopy

　　DeepCopy