C#设计模式之Visitor访问者模式解决长隆欢乐世界问题实例

2020-01-24 00:28:23

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本文实例讲述了C#设计模式之Visitor访问者模式解决长隆欢乐世界问题。分享给大家供大家参考，具体如下：

一、理论定义

访问者模式提供了一组集合对象统一的访问接口，适合对一个集合中的对象，进行逻辑操作，使数据结构和逻辑结构分离。

二、应用举例

需求描述：暑假来啦！三个小伙子组团，开车来长隆欢乐世界玩。
每个人想玩的项目都不一样，
旅游者 1   想玩：十环过山车,龙卷风暴，梦幻旋马
旅游者 2   想玩：空中警察,欢乐摩天轮，超级水战
旅游者 3   想玩：四维影院,垂直极限，U型滑板
车开到长隆后，就开始各自Enjoy啦！！！

三、具体编码

1.一个旅游者接口，里面有一个Play游玩方法

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Com.Design.Gof.Visitor{  public interface ITourist  {    /// <summary>    /// 游玩    /// </summary>    /// <param name="happyWorld">长隆欢乐世界</param>     void Play(ChangLongHappyWorld happyWorld);  }}

2.每个人要玩什么项目，都有一个标志

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Com.Design.Gof.Visitor{  [AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = false)]  public class PlayAttribute : Attribute  {    private string _PlayItem;    /// <summary>    /// 游玩的项目    /// </summary>    public string PlayItem    {      get { return _PlayItem; }      set { _PlayItem = value; }    }  }}

3.长隆欢乐世界

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Reflection;namespace Com.Design.Gof.Visitor{  /// <summary>  /// 长隆欢乐世界  /// </summary>  public class ChangLongHappyWorld  {    /// <summary>    /// 接待各个访问者    /// </summary>    /// <param name="visitor"></param>    public void visit(ITourist visitor) {      //每个旅游者想玩的项目不一样。使用反射，方便调用      MethodInfo[] method = visitor.GetType().GetMethods();      foreach (MethodInfo m in method) {        object[] property= m.GetCustomAttributes(false);        string customerAttribute = null;        if (property.Length>0) {          customerAttribute = property[0].ToString();        }        if (customerAttribute == "Com.Design.Gof.Visitor.PlayAttribute")        {          m.Invoke(visitor, new object[] { });        }      }    }  }}

4.旅游者 1

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Com.Design.Gof.Visitor{  /// <summary>  /// 旅游者 1  想玩：十环过山车,龙卷风暴，梦幻旋马  /// </summary>  public class TouristOne : ITourist  {    /// <summary>    /// 十环过山车    /// </summary>    [PlayAttribute(PlayItem = "TenthRingRollerCoaster")]    public void Play_TenthRingRollerCoaster() {      Console.WriteLine("我是游客1，我现在玩的是：十环过山车");    }    /// <summary>    /// 龙卷风暴    /// </summary>     [PlayAttribute(PlayItem = "TornadoStorm")]    public void Play_TornadoStorm()    {      Console.WriteLine("我是游客1，我现在玩的是：龙卷风暴");    }    /// <summary>    /// 梦幻旋马    /// </summary>    [PlayAttribute(PlayItem = "DreamHorse")]    public void Play_DreamHorse()    {      Console.WriteLine("我是游客1，我现在玩的是：梦幻旋马");    }    public void Play(ChangLongHappyWorld happyWorld)    {      happyWorld.visit(this);    }  }}

5.旅游者 2

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Com.Design.Gof.Visitor{  /// <summary>  /// 旅游者 2  想玩：空中警察,欢乐摩天轮，超级水战  /// </summary>  public class TouristTwo : ITourist  {    /// <summary>    /// 空中警察    /// </summary>    [PlayAttribute(PlayItem = "AirPolice")]    public void Play_AirPolice() {      Console.WriteLine("我是游客2，我现在玩的是：空中警察");    }    /// <summary>    /// 欢乐摩天轮    /// </summary>    [PlayAttribute(PlayItem = "FerrisWheel")]    public void Play_FerrisWheel()    {      Console.WriteLine("我是游客2，我现在玩的是：欢乐摩天轮");    }    /// <summary>    /// 超级水战    /// </summary>    [PlayAttribute(PlayItem = "SuperWater")]    public void Play_SuperWater()    {      Console.WriteLine("我是游客2，我现在玩的是：超级水战");    }    public void Play(ChangLongHappyWorld happyWorld)    {      happyWorld.visit(this);    }  }}

6.旅游者 3

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Com.Design.Gof.Visitor{  /// <summary>  /// 旅游者 3  想玩：四维影院,垂直极限，U型滑板  /// </summary>  public class TouristThree : ITourist  {    /// <summary>    /// 四维影院    /// </summary>    [PlayAttribute(PlayItem = "AirPolice")]    public void Play_Cinema4D() {      Console.WriteLine("我是游客3，我现在玩的是：四维影院");    }    /// <summary>    /// 垂直极限    /// </summary>    [PlayAttribute(PlayItem = "VerticalLimit")]    public void Play_VerticalLimit()    {      Console.WriteLine("我是游客3，我现在玩的是：垂直极限");    }    /// <summary>    /// U型滑板    /// </summary>    [PlayAttribute(PlayItem = "UShapeSkateboard")]    public void Play_UShapeSkateboard()    {      Console.WriteLine("我是游客3，我现在玩的是：U型滑板");    }    public void Play(ChangLongHappyWorld happyWorld)    {      happyWorld.visit(this);    }  }}

7.主函数

using System;using System.Collections.Generic;using System.Linq;using System.Text;using Com.Design.Gof.Visitor;namespace Com.Design.Gof.Test{  class Program  {    static void Main(string[] args)    {      //三个小伙子，开车到长隆欢乐世界 游玩， 每个人想玩的项目都不一样。      List<ITourist> list = new List<ITourist> {       new TouristOne(),       new TouristTwo(),       new TouristThree()      };      //车开到了长隆 南大门，长隆到了      ChangLongHappyWorld happyWorld = new ChangLongHappyWorld();      //开始 游玩 长隆啦！！      foreach (var visit in list) {        visit.Play(happyWorld);        Console.WriteLine("------------------------------------------------");      }      Console.ReadKey();    }  }}

8.运行结果