中介者模式(Mediator Pattern)

冷不防 2022-03-31 03:12 216阅读 0赞

[设计模式 - 吕震宇][-]

[.NET设计模式系列文章][.NET]

[薛敬明的专栏][Link 1]

[乐在其中设计模式(C\#)][C]

# [乐在其中设计模式(C\#) - 中介者模式(Mediator Pattern)][C_ - _Mediator Pattern] #

乐在其中设计模式(C\#) - 中介者模式(Mediator Pattern)

作者： [webabcd][]  
  
  
介绍  
用一个中介对象来封装一系列的对象交互。中介者使各对象不需要显式地相互引用，从而使其耦合松散，而且可以独立地改变它们之间的交互。  
  
  
示例  
有一个Message实体类，某个对象对它的操作有Send()和Insert()方法，现在用一个中介对象来封装这一系列的对象交互。  
![o_Mediator.png][]  
  
  
MessageModel

AbstractMessageMediator

MessageMediator

![None.gif][] using System; 
![None.gif][] using System.Collections.Generic; 
![None.gif][] using System.Text; 
![None.gif][] 
![None.gif][] namespace Pattern.Mediator 
![ExpandedBlockStart.gif][] \{ 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 中介者（ConcreteMediator） 
![ExpandedSubBlockEnd.gif][]///</summary> 
![InBlock.gif][]publicclass MessageMediator : AbstractMessageMediator 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]private Dictionary<string, AbstractMessage> \_dictionary =new Dictionary<string, AbstractMessage>(); 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 注册一个操作Message的对象 
![InBlock.gif][]///</summary> 
![ExpandedSubBlockEnd.gif][]///<param name="abstractMessage">AbstractMessage</param> 
![InBlock.gif][]publicoverridevoid Register(AbstractMessage abstractMessage) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]if (!\_dictionary.ContainsKey(abstractMessage.UserId)) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][] \_dictionary.Add(abstractMessage.UserId, abstractMessage); 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![InBlock.gif][] abstractMessage.AbstractMessageMediator =this; 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 发送Message 
![InBlock.gif][]///</summary> 
![InBlock.gif][]///<param name="from">来自UserId</param> 
![InBlock.gif][]///<param name="to">发送到UserId</param> 
![InBlock.gif][]///<param name="mm">Message实体对象</param> 
![ExpandedSubBlockEnd.gif][]///<returns></returns> 
![InBlock.gif][]publicoverridestring Send(string from, string to, MessageModel mm) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][] AbstractMessage abstractMessage = \_dictionary\[to\]; 
![InBlock.gif][]if (abstractMessage !=null) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]return abstractMessage.Insert(from, mm); 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][]else 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]returnnull; 
![ExpandedSubBlockEnd.gif][] \} 
![ExpandedSubBlockEnd.gif][] \} 
![ExpandedSubBlockEnd.gif][] \} 
![ExpandedBlockEnd.gif][]\} 
![None.gif][]

AbstractMessage

![None.gif][] using System; 
![None.gif][] using System.Collections.Generic; 
![None.gif][] using System.Text; 
![None.gif][] 
![None.gif][] namespace Pattern.Mediator 
![ExpandedBlockStart.gif][] \{ 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 操作Message抽象类（Colleague） 
![ExpandedSubBlockEnd.gif][]///</summary> 
![InBlock.gif][]publicabstractclass AbstractMessage 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]private AbstractMessageMediator \_abstractMessageMediator; 
![InBlock.gif][]privatestring \_userId; 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 构造函数 
![InBlock.gif][]///</summary> 
![ExpandedSubBlockEnd.gif][]///<param name="userId">UserId</param> 
![InBlock.gif][]public AbstractMessage(string userId) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]this.\_userId = userId; 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// UserId 
![ExpandedSubBlockEnd.gif][]///</summary> 
![InBlock.gif][]publicstring UserId 
![ExpandedSubBlockStart.gif][]\{ 
![ExpandedSubBlockStart.gif][]get\{ return \_userId; \} 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 中介者 
![ExpandedSubBlockEnd.gif][]///</summary> 
![InBlock.gif][]public AbstractMessageMediator AbstractMessageMediator 
![ExpandedSubBlockStart.gif][]\{ 
![ExpandedSubBlockStart.gif][]get\{ return \_abstractMessageMediator; \} 
![ExpandedSubBlockStart.gif][]set\{ \_abstractMessageMediator = value; \} 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 发送Message（由客户端调用） 
![InBlock.gif][]///</summary> 
![InBlock.gif][]///<param name="to">发送到UserId</param> 
![InBlock.gif][]///<param name="mm">Message实体对象</param> 
![ExpandedSubBlockEnd.gif][]///<returns></returns> 
![InBlock.gif][]publicstring Send(string to, MessageModel mm) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][]return \_abstractMessageMediator.Send(\_userId, to, mm); 
![ExpandedSubBlockEnd.gif][] \} 
![InBlock.gif][] 
![ExpandedSubBlockStart.gif][]///<summary> 
![InBlock.gif][]/// 接受Message（由中介者调用） 
![InBlock.gif][]///</summary> 
![InBlock.gif][]///<param name="from">来自UserId</param> 
![InBlock.gif][]///<param name="mm">Message实体对象</param> 
![ExpandedSubBlockEnd.gif][]///<returns></returns> 
![InBlock.gif][]publicabstractstring Insert(string from, MessageModel mm); 
![ExpandedSubBlockEnd.gif][] \} 
![ExpandedBlockEnd.gif][]\} 
![None.gif][]

SqlMessage

XmlMessage

Test

![None.gif][] using System; 
![None.gif][] using System.Data; 
![None.gif][] using System.Configuration; 
![None.gif][] using System.Collections; 
![None.gif][] using System.Web; 
![None.gif][] using System.Web.Security; 
![None.gif][] using System.Web.UI; 
![None.gif][] using System.Web.UI.WebControls; 
![None.gif][] using System.Web.UI.WebControls.WebParts; 
![None.gif][] using System.Web.UI.HtmlControls; 
![None.gif][] 
![None.gif][] using Pattern.Mediator; 
![None.gif][] 
![None.gif][] public partial class Mediator : System.Web.UI.Page 
![ExpandedBlockStart.gif][] \{ 
![InBlock.gif][]protectedvoid Page\_Load(object sender, EventArgs e) 
![ExpandedSubBlockStart.gif][]\{ 
![InBlock.gif][] AbstractMessageMediator messageMediator =new MessageMediator(); 
![InBlock.gif][] 
![InBlock.gif][] AbstractMessage user1 =new SqlMessage("user1"); 
![InBlock.gif][] AbstractMessage user2 =new SqlMessage("user2"); 
![InBlock.gif][] AbstractMessage user3 =new XmlMessage("user3"); 
![InBlock.gif][] AbstractMessage user4 =new XmlMessage("user4"); 
![InBlock.gif][] 
![InBlock.gif][] messageMediator.Register(user1); 
![InBlock.gif][] messageMediator.Register(user2); 
![InBlock.gif][] messageMediator.Register(user3); 
![InBlock.gif][] messageMediator.Register(user4); 
![InBlock.gif][] 
![InBlock.gif][] Response.Write(user1.Send("user2", new MessageModel("你好！", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![InBlock.gif][] Response.Write(user2.Send("user1", new MessageModel("我不好！", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![InBlock.gif][] Response.Write(user1.Send("user2", new MessageModel("不好就不好吧。", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![InBlock.gif][] Response.Write(user3.Send("user4", new MessageModel("吃了吗？", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![InBlock.gif][] Response.Write(user4.Send("user3", new MessageModel("没吃，你请我？", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![InBlock.gif][] Response.Write(user3.Send("user4", new MessageModel("不请。", DateTime.Now))); 
![InBlock.gif][] Response.Write(" "); 
![ExpandedSubBlockEnd.gif][] \} 
![ExpandedBlockEnd.gif][]\} 
![None.gif][]

运行结果  
Sql方式插入Message（user1发送给user2） - 内容：你好！ - 时间：2007-5-19 23:43:19  
Sql方式插入Message（user2发送给user1） - 内容：我不好！ - 时间：2007-5-19 23:43:19  
Sql方式插入Message（user1发送给user2） - 内容：不好就不好吧。 - 时间：2007-5-19 23:43:19  
Xml方式插入Message（user3发送给user4） - 内容：吃了吗？ - 时间：2007-5-19 23:43:19  
Xml方式插入Message（user4发送给user3） - 内容：没吃，你请我？ - 时间：2007-5-19 23:43:19  
Xml方式插入Message（user3发送给user4） - 内容：不请。 - 时间：2007-5-19 23:43:19  
  
  
参考  
[http://www.dofactory.com/Patterns/PatternMediator.aspx][http_www.dofactory.com_Patterns_PatternMediator.aspx]  
  
  
OK  
[\[源码下载\]][Link 2]

# [设计模式22：Mediator Pattern (调解者模式)][22_Mediator Pattern] #

英文原文：[http://www.dofactory.com/Patterns/PatternMediator.aspx][http_www.dofactory.com_Patterns_PatternMediator.aspx]

### 一、Mediator Pattern (调解者模式)的定义 ###

Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it lets you vary their interaction independently.

定义一个对象将一系列对象如何相互作用的操作进行封装。调解者通过避免一个对象明确指向其余的对象来促使自由耦合，同时能够让你单独的改变他们之间的相互作用。

### 二、UML类图 ###

![Median][]

* **Mediator** **(IChatroom)**
 
 * 定义一个接口用于与同事级对象进行通信
 * **ConcreteMediator** **(Chatroom)**
 
 * 通过与同事级对象进行对等来实现相互协作行为
 * 知道并且维持本身的同事级对象
 * **Colleague classes** **(Participant)**
 
 * 每个同事级对象都知道自己的调节者对象
 * 每个同事级对象在与另外的同事级对象进行通信时必须要与调节者进行通信。
 
 ### 三、调解者模式实例代码 ###
 
 **\[c-sharp\]** [ view plain][view plain] [copy][view plain]
 
 1. using System;
 2. using System.Collections.Generic;
 3. using System.Linq;
 4. using System.Text;
 5. 
 6. namespace Mediator\_Pattern
 7. \{
 8. /// <summary>
 9. 
 10. /// MainApp startup class for Structural 
 11. 
 12. /// Mediator Design Pattern.
 13. 
 14. /// </summary>
 15. 
 16. class MainApp
 17. \{
 18. 
 19. /// <summary>
 20. 
 21. /// Entry point into console application.
 22. 
 23. /// </summary>
 24. 
 25. static void Main()
 26. \{
 27. 
 28. ConcreteMediator m = new ConcreteMediator();
 29. 
 30. 
 31. 
 32. ConcreteColleague1 c1 = new ConcreteColleague1(m);
 33. 
 34. ConcreteColleague2 c2 = new ConcreteColleague2(m);
 35. 
 36. 
 37. 
 38. m.Colleague1 = c1;
 39. 
 40. m.Colleague2 = c2;
 41. 
 42. 
 43. 
 44. c1.Send("How are you?");
 45. 
 46. c2.Send("Fine, thanks");
 47. 
 48. 
 49. 
 50. // Wait for user
 51. 
 52. Console.ReadKey();
 53. 
 54. \}
 55. 
 56. \}
 57. 
 58. 
 59. 
 60. /// <summary>
 61. 
 62. /// The 'Mediator' abstract class
 63. 
 64. /// </summary>
 65. 
 66. abstract class Mediator
 67. \{
 68. 
 69. public abstract void Send(string message,
 70. 
 71. Colleague colleague);
 72. 
 73. \}
 74. 
 75. 
 76. 
 77. /// <summary>
 78. 
 79. /// The 'ConcreteMediator' class
 80. 
 81. /// </summary>
 82. 
 83. class ConcreteMediator : Mediator
 84. \{
 85. 
 86. private ConcreteColleague1 \_colleague1;
 87. 
 88. private ConcreteColleague2 \_colleague2;
 89. 
 90. 
 91. 
 92. public ConcreteColleague1 Colleague1
 93. \{
 94. 
 95. set \{ \_colleague1 = value; \}
 96. 
 97. \}
 98. 
 99. 
 100. 
 101. public ConcreteColleague2 Colleague2
 102. \{
 103. 
 104. set \{ \_colleague2 = value; \}
 105. 
 106. \}
 107. 
 108. 
 109. 
 110. public override void Send(string message,
 111. 
 112. Colleague colleague)
 113. \{
 114. 
 115. if (colleague == \_colleague1)
 116. \{
 117. 
 118. \_colleague2.Notify(message);
 119. 
 120. \}
 121. 
 122. else
 123. \{
 124. 
 125. \_colleague1.Notify(message);
 126. 
 127. \}
 128. 
 129. \}
 130. 
 131. \}
 132. 
 133. 
 134. 
 135. /// <summary>
 136. 
 137. /// The 'Colleague' abstract class
 138. 
 139. /// </summary>
 140. 
 141. abstract class Colleague
 142. \{
 143. 
 144. protected Mediator mediator;
 145. 
 146. 
 147. 
 148. // Constructor
 149. 
 150. public Colleague(Mediator mediator)
 151. \{
 152. 
 153. this.mediator = mediator;
 154. 
 155. \}
 156. 
 157. \}
 158. 
 159. 
 160. 
 161. /// <summary>
 162. 
 163. /// A 'ConcreteColleague' class
 164. 
 165. /// </summary>
 166. 
 167. class ConcreteColleague1 : Colleague
 168. \{
 169. 
 170. // Constructor
 171. 
 172. public ConcreteColleague1(Mediator mediator)
 173. 
 174. : base(mediator)
 175. \{
 176. 
 177. \}
 178. 
 179. 
 180. 
 181. public void Send(string message)
 182. \{
 183. 
 184. mediator.Send(message, this);
 185. 
 186. \}
 187. 
 188. 
 189. 
 190. public void Notify(string message)
 191. \{
 192. 
 193. Console.WriteLine("Colleague1 gets message: "
 194. 
 195. \+ message);
 196. 
 197. \}
 198. 
 199. \}
 200. 
 201. 
 202. 
 203. /// <summary>
 204. 
 205. /// A 'ConcreteColleague' class
 206. 
 207. /// </summary>
 208. 
 209. class ConcreteColleague2 : Colleague
 210. \{
 211. 
 212. // Constructor
 213. 
 214. public ConcreteColleague2(Mediator mediator)
 215. 
 216. : base(mediator)
 217. \{
 218. 
 219. \}
 220. 
 221. 
 222. 
 223. public void Send(string message)
 224. \{
 225. 
 226. mediator.Send(message, this);
 227. 
 228. \}
 229. 
 230. 
 231. 
 232. public void Notify(string message)
 233. \{
 234. 
 235. Console.WriteLine("Colleague2 gets message: "
 236. 
 237. \+ message);
 238. 
 239. \}
 240. 
 241. \}
 242. \}
 
 ### 四、另外一个使用调解者模式的实例代码 ###
 
 This real-world code demonstrates the Mediator pattern facilitating loosely coupled communication between different Participants registering with a Chatroom. The Chatroom is the central hub through which all communication takes place. At this point only one-to-one communication is implemented in the Chatroom, but would be trivial to change to one-to-many.
 
 **\[c-sharp\]** [ view plain][view plain] [copy][view plain]
 
 1. using System;
 2. using System.Collections.Generic;
 3. using System.Linq;
 4. using System.Text;
 5. 
 6. namespace Mediator\_Pattern
 7. \{
 8. /// <summary>
 9. 
 10. /// MainApp startup class for Real-World 
 11. 
 12. /// Mediator Design Pattern.
 13. 
 14. /// </summary>
 15. 
 16. class MainApp
 17. \{
 18. 
 19. /// <summary>
 20. 
 21. /// Entry point into console application.
 22. 
 23. /// </summary>
 24. 
 25. static void Main()
 26. \{
 27. 
 28. // Create chatroom
 29. 
 30. Chatroom chatroom = new Chatroom();
 31. 
 32. 
 33. 
 34. // Create participants and register them
 35. 
 36. Participant George = new Beatle("George");
 37. 
 38. Participant Paul = new Beatle("Paul");
 39. 
 40. Participant Ringo = new Beatle("Ringo");
 41. 
 42. Participant John = new Beatle("John");
 43. 
 44. Participant Yoko = new NonBeatle("Yoko");
 45. 
 46. 
 47. 
 48. chatroom.Register(George);
 49. 
 50. chatroom.Register(Paul);
 51. 
 52. chatroom.Register(Ringo);
 53. 
 54. chatroom.Register(John);
 55. 
 56. chatroom.Register(Yoko);
 57. 
 58. 
 59. 
 60. // Chatting participants
 61. 
 62. Yoko.Send("John", "Hi John!");
 63. 
 64. Paul.Send("Ringo", "All you need is love");
 65. 
 66. Ringo.Send("George", "My sweet Lord");
 67. 
 68. Paul.Send("John", "Can't buy me love");
 69. 
 70. John.Send("Yoko", "My sweet love");
 71. 
 72. 
 73. 
 74. // Wait for user
 75. 
 76. Console.ReadKey();
 77. 
 78. \}
 79. 
 80. \}
 81. 
 82. 
 83. 
 84. /// <summary>
 85. 
 86. /// The 'Mediator' abstract class
 87. 
 88. /// </summary>
 89. 
 90. abstract class AbstractChatroom
 91. \{
 92. 
 93. public abstract void Register(Participant participant);
 94. 
 95. public abstract void Send(
 96. 
 97. string from, string to, string message);
 98. 
 99. \}
 100. 
 101. 
 102. 
 103. /// <summary>
 104. 
 105. /// The 'ConcreteMediator' class
 106. 
 107. /// </summary>
 108. 
 109. class Chatroom : AbstractChatroom
 110. \{
 111. 
 112. private Dictionary<string, Participant> \_participants =
 113. 
 114. new Dictionary<string, Participant>();
 115. 
 116. 
 117. 
 118. public override void Register(Participant participant)
 119. \{
 120. 
 121. if (!\_participants.ContainsValue(participant))
 122. \{
 123. 
 124. \_participants\[participant.Name\] = participant;
 125. 
 126. \}
 127. 
 128. 
 129. 
 130. participant.Chatroom = this;
 131. 
 132. \}
 133. 
 134. 
 135. 
 136. public override void Send(
 137. 
 138. string from, string to, string message)
 139. \{
 140. 
 141. Participant participant = \_participants\[to\];
 142. 
 143. 
 144. 
 145. if (participant != null)
 146. \{
 147. 
 148. participant.Receive(from, message);
 149. 
 150. \}
 151. 
 152. \}
 153. 
 154. \}
 155. 
 156. 
 157. 
 158. /// <summary>
 159. 
 160. /// The 'AbstractColleague' class
 161. 
 162. /// </summary>
 163. 
 164. class Participant
 165. \{
 166. 
 167. private Chatroom \_chatroom;
 168. 
 169. private string \_name;
 170. 
 171. 
 172. 
 173. // Constructor
 174. 
 175. public Participant(string name)
 176. \{
 177. 
 178. this.\_name = name;
 179. 
 180. \}
 181. 
 182. 
 183. 
 184. // Gets participant name
 185. 
 186. public string Name
 187. \{
 188. 
 189. get \{ return \_name; \}
 190. 
 191. \}
 192. 
 193. 
 194. 
 195. // Gets chatroom
 196. 
 197. public Chatroom Chatroom
 198. \{
 199. 
 200. set \{ \_chatroom = value; \}
 201. 
 202. get \{ return \_chatroom; \}
 203. 
 204. \}
 205. 
 206. 
 207. 
 208. // Sends message to given participant
 209. 
 210. public void Send(string to, string message)
 211. \{
 212. 
 213. \_chatroom.Send(\_name, to, message);
 214. 
 215. \}
 216. 
 217. 
 218. 
 219. // Receives message from given participant
 220. 
 221. public virtual void Receive(
 222. 
 223. string from, string message)
 224. \{
 225. 
 226. Console.WriteLine("\{0\} to \{1\}: '\{2\}'",
 227. 
 228. from, Name, message);
 229. 
 230. \}
 231. 
 232. \}
 233. 
 234. 
 235. 
 236. /// <summary>
 237. 
 238. /// A 'ConcreteColleague' class
 239. 
 240. /// </summary>
 241. 
 242. class Beatle : Participant
 243. \{
 244. 
 245. // Constructor
 246. 
 247. public Beatle(string name)
 248. 
 249. : base(name)
 250. \{
 251. 
 252. \}
 253. 
 254. 
 255. 
 256. public override void Receive(string from, string message)
 257. \{
 258. 
 259. Console.Write("To a Beatle: ");
 260. 
 261. base.Receive(from, message);
 262. 
 263. \}
 264. 
 265. \}
 266. 
 267. 
 268. 
 269. /// <summary>
 270. 
 271. /// A 'ConcreteColleague' class
 272. 
 273. /// </summary>
 274. 
 275. class NonBeatle : Participant
 276. \{
 277. 
 278. // Constructor
 279. 
 280. public NonBeatle(string name)
 281. 
 282. : base(name)
 283. \{
 284. 
 285. \}
 286. 
 287. 
 288. 
 289. public override void Receive(string from, string message)
 290. \{
 291. 
 292. Console.Write("To a non-Beatle: ");
 293. 
 294. base.Receive(from, message);
 295. 
 296. \}
 297. 
 298. \}
 299. \}
 
 ## 四．中介者模式案例分析（Example） ##
 
 ### 1、场景 ###
 
 实现一个聊天室功能，聊城室就是一个中介者，参与聊天的人就是同事对象,如下图所示
 
 ![Mediator_Pattern_Example.jpg][]
 
 **AbstractChatroom类**：抽象聊天室类，做为Participant的交互的中介。
 
 Register()方法:会员注册功能；Send()方法：发送消息功能。
 
 **Chatroom类**：具体聊天室类，实现抽象聊天室类中的方法。
 
 **Participant类**：参与者类，主要有发送消息Send()功能和接受消息Receive()功能。
 
 **Beatle类，NonBeatle类**：参与者类的具体实现，实现父类Paticipant类中的方法。
 
 ### 2、代码 ###
 
 <table style="border-bottom:medium none; border-left:medium none; margin:auto auto auto 21pt; border-collapse:collapse; border-top:medium none; border-right:medium none"> 
 <tbody> 
 <tr> 
 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; background:#f3f3f3; border-top:windowtext 1pt solid; border-right:windowtext 1pt solid; padding-top:0cm"> 1、抽象聊天室类AbstractChatroom及其具体聊天室Chatroom </td> 
 </tr> 
 <tr style="height:21.75pt"> 
 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; height:21.75pt; border-top:#d4d0c8; border-right:windowtext 1pt solid; padding-top:0cm"> /// &lt;summary&gt; /// The 'Mediator' abstract class /// &lt;/summary&gt; abstract class AbstractChatroom { &nbsp;&nbsp;&nbsp; public abstract void Register(Participant participant); &nbsp;&nbsp;&nbsp; public abstract void Send(string from, string to, string message); } /// &lt;summary&gt; /// The 'ConcreteMediator' class /// &lt;/summary&gt; class Chatroom : AbstractChatroom { &nbsp;&nbsp;&nbsp; private Dictionary&lt;string, Participant&gt; _participants =new Dictionary&lt;string, Participant&gt;(); &nbsp;&nbsp;&nbsp; public override void Register(Participant participant) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if (!_participants.ContainsValue(participant)) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; _participants[participant.Name] = participant; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; participant.Chatroom = this; &nbsp; &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; public override void Send(string from, string to, string message) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Participant participant = _participants[to]; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if (participant != null) &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; participant.Receive(from, message); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; } } </td> 
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 <table style="border-bottom:medium none; border-left:medium none; margin:auto auto auto 21pt; border-collapse:collapse; border-top:medium none; border-right:medium none"> 
 <tbody> 
 <tr> 
 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; background:#f3f3f3; border-top:windowtext 1pt solid; border-right:windowtext 1pt solid; padding-top:0cm"> 2、参与者Participant类及其实现Beatle、NonBeatle </td> 
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 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:windowtext 1pt solid; padding-top:0cm"> /// &lt;summary&gt; /// The 'AbstractColleague' class /// &lt;/summary&gt; class Participant { &nbsp;&nbsp;&nbsp; private Chatroom _chatroom; &nbsp;&nbsp;&nbsp; private string _name; &nbsp;&nbsp;&nbsp;// Constructor &nbsp;&nbsp;&nbsp; public Participant(string name) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; this._name = name; &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; // Gets participant name &nbsp;&nbsp;&nbsp; public string Name &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; get { return _name; } &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; // Gets chatroom &nbsp;&nbsp;&nbsp; public Chatroom Chatroom &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; set { _chatroom = value; } &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; get { return _chatroom; } &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; // Sends message to given participant &nbsp;&nbsp;&nbsp; public void Send(string to, string message) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; _chatroom.Send(_name, to, message); &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; // Receives message from given participant &nbsp;&nbsp;&nbsp;public virtual void Receive(string from, string message) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Console.WriteLine("{0} to {1}: '{2}'",from, Name, message); &nbsp;&nbsp;&nbsp; } } /// &lt;summary&gt; /// A 'ConcreteColleague' class /// &lt;/summary&gt; class Beatle : Participant { &nbsp;&nbsp;&nbsp; // Constructor &nbsp;&nbsp;&nbsp; public Beatle(string name) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; : base(name) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; public override void Receive(string from, string message) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Console.Write("To a Beatle: "); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; base.Receive(from, message); &nbsp;&nbsp;&nbsp; } } /// &lt;summary&gt; /// A 'ConcreteColleague' class /// &lt;/summary&gt; class NonBeatle : Participant { &nbsp;&nbsp;&nbsp; // Constructor &nbsp;&nbsp;&nbsp; public NonBeatle(string name) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; : base(name) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp; public override void Receive(string from, string message) &nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Console.Write("To a non-Beatle: "); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; base.Receive(from, message); &nbsp;&nbsp;&nbsp; } } </td> 
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 <table style="border-bottom:medium none; border-left:medium none; margin:auto auto auto 21pt; border-collapse:collapse; border-top:medium none; border-right:medium none"> 
 <tbody> 
 <tr> 
 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; background:#f3f3f3; border-top:windowtext 1pt solid; border-right:windowtext 1pt solid; padding-top:0cm"> 3、客户端代码 </td> 
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 <td style="border-bottom:windowtext 1pt solid; border-left:windowtext 1pt solid; padding-bottom:0cm; background-color:transparent; padding-left:5.4pt; width:405.1pt; padding-right:5.4pt; border-top:#d4d0c8; border-right:windowtext 1pt solid; padding-top:0cm"> static void Main(string[] args) { &nbsp;&nbsp;&nbsp; // Create chatroom &nbsp;&nbsp;&nbsp; Chatroom chatroom = new Chatroom(); &nbsp;&nbsp;&nbsp; // Create participants and register them &nbsp;&nbsp;&nbsp; Participant George = new Beatle("George"); &nbsp;&nbsp;&nbsp; Participant Paul = new Beatle("Paul"); &nbsp;&nbsp;&nbsp; Participant Ringo = new Beatle("Ringo"); &nbsp;&nbsp;&nbsp; Participant John = new Beatle("John"); &nbsp;&nbsp;&nbsp; Participant Yoko = new NonBeatle("Yoko"); &nbsp; &nbsp;&nbsp;&nbsp; chatroom.Register(George); &nbsp;&nbsp;&nbsp; chatroom.Register(Paul); &nbsp;&nbsp;&nbsp; chatroom.Register(Ringo); &nbsp;&nbsp;&nbsp; chatroom.Register(John); &nbsp;&nbsp;&nbsp; chatroom.Register(Yoko); &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; // Chatting participants &nbsp;&nbsp;&nbsp; Yoko.Send("John", "Hi John!"); &nbsp;&nbsp;&nbsp; Paul.Send("Ringo", "All you need is love"); &nbsp;&nbsp;&nbsp; Ringo.Send("George", "My sweet Lord"); &nbsp;&nbsp;&nbsp; Paul.Send("John", "Can't buy me love"); &nbsp;&nbsp; &nbsp;John.Send("Yoko", "My sweet love"); &nbsp;&nbsp;&nbsp; // Wait for user &nbsp;&nbsp;&nbsp; Console.ReadKey(); } </td> 
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 ### 3、运行结果 ###
 
 ![Mediator_Pattern_Example_Result.jpg][]
 
 ## 五、总结（Summary） ##
 
 中介者模式（Mediator Pattern），定义一个中介对象来封装系列对象之间的交互。中介者使各个对象不需要显示地相互引用，从而使其耦合性松散，而且可以独立地改变他们之间的交互。中介者模式一般应用于一组对象以定义良好但是复杂的方法进行通信的场合，以及想定制一个分布在多个类中的行为，而不想生成太多的子类的场合。

[-]: http://www.cnblogs.com/zhenyulu/category/6930.html
[.NET]: http://www.cnblogs.com/Terrylee/archive/2006/07/17/334911.html
[Link 1]: http://blog.csdn.net/rocket5725/article/category/559017
[C]: http://www.cnblogs.com/webabcd/category/82668.html
[C_ - _Mediator Pattern]: http://www.cnblogs.com/webabcd/archive/2007/05/19/752808.html
[webabcd]: http://webabcd.cnblogs.com/
[o_Mediator.png]: /images/20220331/19163c2816ff4f469d3f55c0ca6f37aa.png
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[http_www.dofactory.com_Patterns_PatternMediator.aspx]: http://www.dofactory.com/Patterns/PatternMediator.aspx
[Link 2]: http://files.cnblogs.com/webabcd/Pattern.rar
[22_Mediator Pattern]: http://blog.csdn.net/rocket5725/article/details/4334040
[Median]: /images/20220331/17512279058c41f8a50375ba985d3992.png
[view plain]: http://blog.csdn.net/rocket5725/article/details/4334040#
[Mediator_Pattern_Example.jpg]: /images/20220331/8c17ebdd4c14415086111f4c593fa184.png
[Mediator_Pattern_Example_Result.jpg]: /images/20220331/8e3e254ddd0140fbae7d5b838b8d069f.png