设计模式之桥接模式

　　1，多重继承变化封装

　　2，桥接模式：解决多维度的变化

　　有一个手机抽象类如下：

 1     /// <summary>
 2     /// 抽象父类
 3     /// </summary>
 4     public abstract class BasePhone
 5     {
 6         /// <summary>
 7         /// 操作系统
 8         /// </summary>
 9         public abstract string System();
10 
11         /// <summary>
12         /// 系统版本
13         /// </summary>
14         public abstract string Version();
15         /// <summary>
16         /// 打电话
17         /// </summary>
18         public abstract void Call();
19         /// <summary>
20         /// 发短信
21         /// </summary>
22         public abstract void Text();
23     }

　　（1）现在我们想要一个iPhone和Galaxy，则需要代码如下：

 1  public class iPhone : BasePhone
 2     {
 3         public override string System()
 4         {
 5             return "IOS";
 6         }
 7         public override string Version()
 8         {
 9             return "9.3";
10         }
11         public override void Call()
12         {
13             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.System(), this.Version());
14         }
15 
16         public override void Text()
17         {
18             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.System(), this.Version());
19         }
20     }
21 
22     public class Galaxy:BasePhone
23     {
24         public override string System()
25         {
26             return "Android";
27         }
28 
29         public override string Version()
30         {
31             return "6.0";
32         }
33 
34         public override void Call()
35         {
36             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.System(), this.Version());
37         }
38 
39         public override void Text()
40         {
41             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.System(), this.Version());
42         }
43     }

　　调用如下：

 1             {
 2                 BasePhone phone=new iPhone();
 3                 phone.Call();
 4                 phone.Text();
 5             }
 6             {
 7                 BasePhone phone=new Galaxy();
 8                 phone.Call();
 9                 phone.Text();
10             }

　　（2）如果现在我们想要刷机，将iPhone手机装Android系统，将Galaxy装IOS系统，则需要代码如下：

 1   /// <summary>
 2     /// 使用Android系统的iPhone手机
 3     /// </summary>
 4     public class iPhoneAndroid:BasePhone
 5     {
 6         public override string System()
 7         {
 8             return "Android";
 9         }
10 
11         public override string Version()
12         {
13             return "6.0";
14         }
15 
16         public override void Call()
17         {
18             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.System(), this.Version());
19         }
20 
21         public override void Text()
22         {
23             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.System(), this.Version());
24         }
25     }
26 
27     public class GalaxyIOS : BasePhone
28     {
29         public override string System()
30         {
31             return "IOS";
32         }
33         public override string Version()
34         {
35             return "9.3";
36         }
37         public override void Call()
38         {
39             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.System(), this.Version());
40         }
41 
42         public override void Text()
43         {
44             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.System(), this.Version());
45         }
46     }

　　如果还有其它系统的手机，比如WinPhone，则每一款手机将会有iPhone,iPhoneAndroid,iPhoneWinPhone，如果操作系统为M，手机类型为N，则需要多的类的个数为M*N，随着系统和手机类型的增加，将会造成类泛滥，所以现在将变化进行封装，

　　（3）桥接模式

　　代码如下：

 1     public interface ISystem
 2     {
 3         string System();
 4         string Version();
 5     }
 6 
 7     public class AndroidSystem : ISystem
 8     {
 9         public string System()
10         {
11             return "Android";
12         }
13         public string Version()
14         {
15             return "6.0";
16         }
17     }
18 
19     public class IOSSystem: ISystem
20     {
21         public string System()
22         {
23             return "IOS";
24         }
25         public string Version( )
26         {
27             return "9.3";
28         }
29     }
30 
31     public class WinphoneSystem : ISystem
32     {
33         public string System()
34         {
35             return "Winphone";
36         }
37         public string Version()
38         {
39             return "10.0";
40         }
41     }

　　BasePhoneBridge:

 1     /// <summary>
 2     /// 抽象父类
 3     /// </summary>
 4     public abstract class BasePhoneBridge
 5     {
 6         /// <summary>
 7         /// 操作系统
 8         /// </summary>
 9         public ISystem SystemVersion { get; set; }
10         ///// <summary>
11         ///// 操作系统
12         ///// </summary>
13         //public abstract string System();
14 
15         ///// <summary>
16         ///// 系统版本
17         ///// </summary>
18         //public abstract string Version();
19         /// <summary>
20         /// 打电话
21         /// </summary>
22         public abstract void Call();
23         /// <summary>
24         /// 发短信
25         /// </summary>
26         public abstract void Text();
27     }

GalaxyBridge:

 1     public class GalaxyBridge : BasePhoneBridge
 2     {
 3         public override void Call()
 4         {
 5             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
 6         }
 7         public override void Text()
 8         {
 9             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
10         }
11     }

　　iPhoneBridge :

 1     public class iPhoneBridge : BasePhoneBridge
 2     {
 3         public override void Call()
 4         {
 5             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
 6         }
 7         public override void Text()
 8         {
 9             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
10         }
11     }

　　LumiaBridge:

 1     public class LumiaBridge : BasePhoneBridge
 2     {
 3         public override void Call()
 4         {
 5             Console.WriteLine("Use OS{0}.{1}.{2} Call", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
 6         }
 7         public override void Text()
 8         {
 9             Console.WriteLine("Use OS{0}.{1}.{2} Text", this.GetType().Name, this.SystemVersion.System(), this.SystemVersion.Version());
10         }
11     }

　　调用方式：

 1             Console.WriteLine("**************Bridge***************");
 2             ISystem android = new AndroidSystem();
 3             ISystem ios = new IOSSystem();
 4             ISystem winphone = new WinphoneSystem();
 5             {
 6                 BasePhoneBridge phone = new GalaxyBridge();
 7                 phone.SystemVersion = android;
 8                 phone.Call();
 9                 phone.Text();
10             }
11             {
12                 BasePhoneBridge phone = new GalaxyBridge();
13                 phone.SystemVersion = ios;
14                 phone.Call();
15                 phone.Text();
16             }
17             {
18                 BasePhoneBridge phone = new GalaxyBridge();
19                 phone.SystemVersion = winphone;
20                 phone.Call();
21                 phone.Text();
22             }

　　效果：

　　此时，子类数量为操作系统M+手机类型N 个。

　　桥接模式缺点：使用麻烦，对于上端来说需要了解更多细节（需要知道怎么初始化操作系统）