4. 建造者模式

  将一个复杂的构建与其表示相分离，使得同样的构建过程可以创建不同的表示。

 

  1 //门
  2 public abstract class Door
  3     {
  4          public abstract void ShowDoor();
  5     }
  6 //时尚的门
  7 public class ModernDoor:Door
  8     {
  9         public override void ShowDoor()
 10         {
 11             Console.WriteLine("创建了一个时尚的门");
 12         }
 13     }
 14 //墙
 15  public abstract class Wall
 16     {
 17         public abstract void ShowWall();
 18     }
 19 //时尚的墙
 20 public class ModernWall:Wall
 21     {
 22         public override void ShowWall()
 23         {
 24             Console.WriteLine("创建一个时尚在墙");
 25         }
 26     }
 27 //窗
 28  public abstract  class Window
 29     {
 30         public abstract void ShowWindow();
 31     }
 32 //时尚的窗
 33 public class ModernWindow:Window
 34     {
 35         public override void ShowWindow()
 36         {
 37             Console.WriteLine("创建一个时尚在窗");
 38         }
 39     }
 40 //古典的窗
 41 public class OldWindow:Window
 42     {
 43         public override void ShowWindow()
 44         {
 45             Console.WriteLine("创建一古典的窗");
 46         }
 47     }
 48 //房子
 49  public class House
 50     {
 51         public List<Door> doorList=new List<Door>();
 52         public List<Wall> wallList=new List<Wall>();
 53         public List<Window> windowList=new List<Window>();
 54 
 55         public void ShowHouse()
 56         {
 57             foreach (Door door in doorList)
 58             {
 59                 door.ShowDoor();
 60             }
 61             foreach (Wall wall in wallList)
 62             {
 63                 wall.ShowWall();
 64             }
 65             foreach (Window window in windowList)
 66             {
 67                 window.ShowWindow();
 68             }
 69         }
 70     }
 71 //房子建造者
 72 public abstract class HouseBuilder
 73     {
 74         protected House house = new House();
 75 
 76         public abstract void BuildWall();
 77 
 78         public abstract void BuildDoor();
 79 
 80         public abstract void BuildWindow();
 81 
 82         public House GetHouse()
 83         {
 84             return house;
 85         }
 86     }
 87 //时尚的房子建造者
 88 public class ModernHouseBuilder:HouseBuilder
 89     {
 90         public ModernHouseBuilder()
 91         {
 92             BuildWall();
 93             BuildWall();
 94             BuildDoor();
 95             BuildWindow();
 96         }
 97         public override void BuildWall()
 98         {
 99             house.wallList.Add(new ModernWall());
100         }
101 
102         public override void BuildDoor()
103         {
104             house.doorList.Add(new ModernDoor());
105         }
106 
107         public override void BuildWindow()
108         {
109             house.windowList.Add(new ModernWindow());
110             house.windowList.Add(new OldWindow());
111         }
112     }
113 //古典的房子建造者
114 public class OldHouseBuilder:HouseBuilder
115     {
116         public ModernHouseBuilder()
117         {
118             
119             BuildWall();
120             BuildDoor();
121             BuildWindow();
122         }
123         public override void BuildWall()
124         {
125             house.wallList.Add(new ModernWall());
126         }
127 
128         public override void BuildDoor()
129         {
130             house.doorList.Add(new ModernDoor());
131         }
132 
133         public override void BuildWindow()
134         {
135             house.windowList.Add(new OldWindow());
136             house.windowList.Add(new OldWindow());
137         }
138     }
139 //客户端
140 class Program
141     {
142         static void Main(string[] args)
143         {
144             string assembly = ConfigurationManager.AppSettings["Assembly"];
145             string instance = ConfigurationManager.AppSettings["Instance"];
146             HouseBuilder build = (HouseBuilder)Assembly.Load(assembly).
147                 CreateInstance(instance);
148             //HouseBuilder build = new ModernHouseBuilder();
149             House house = build.GetHouse();
150             house.ShowHouse();
151             Console.ReadLine();
152         }
153     }
154 
155 <?xml version="1.0" encoding="utf-8" ?>
156 <configuration>
157   <appSettings>
158     <add key="Assembly" value="Builder"/>
159     <add key="Instance" value="Builder.ModernHouseBuilder"/>
160   </appSettings>
161 </configuration>

房子的建造过程是固定不变的，都是先做墙，后是门窗。 但是墙可以根据情况，选择对应的子库。

最后，都是返回一个对象：房子。