1 using System;
2
3 abstract class Handler
4 {
5 protected Handler successorHandler;
6 abstract public void HandleRequest(Request request);
7 public void SetSuccessor(Handler sucessor)
8 {
9 successorHandler = sucessor;
10 }
11 }
12
13 class ConcreteHandler1 : Handler
14 {
15 override public void HandleRequest(Request request)
16 {
17 // determine if we can handle the request
18 if (request.RequestType == 1) // some complex decision making!
19 {
20 // request handling code goes here
21 Console.WriteLine("request handled in ConcreteHandler1");
22 }
23 else
24 {
25 // not handled here - pass on to next in the chain
26 if (successorHandler != null)
27 successorHandler.HandleRequest(request);
28 }
29 }
30 }
31
32 class ConcreteHandler2 : Handler
33 {
34 override public void HandleRequest(Request request)
35 {
36 // determine if we can handle the request
37 if (request.RequestType == 2) // some complex decision making!
38 {
39 // request handling code goes here
40 Console.WriteLine("request handled in ConcreteHandler2");
41 }
42 else
43 {
44 // not handled here - pass on to next in the chain
45 if (successorHandler != null)
46 successorHandler.HandleRequest(request);
47 }
48 }
49 }
50
51 class ConcreteHandler3 : Handler
52 {
53 override public void HandleRequest(Request request)
54 {
55 // determine if we can handle the request
56 if (request.RequestType == 3) // some complex decision making!
57 {
58 // request handling code goes here
59 Console.WriteLine("request handled in ConcreteHandler3");
60 }
61 else
62 {
63 // not handled here - pass on to next in the chain
64 if (successorHandler != null)
65 successorHandler.HandleRequest(request);
66 }
67 }
68 }
69
70 class Request
71 {
72 private int iRequestType;
73 private string strRequestParameters;
74
75 public Request(int requestType, string requestParameters)
76 {
77 iRequestType = requestType;
78 strRequestParameters = requestParameters;
79 }
80
81 public int RequestType
82 {
83 get
84 {
85 return iRequestType;
86 }
87 set
88 {
89 iRequestType = value;
90 }
91 }
92 }
93
94 /// <summary>
95 /// Summary description for Client.
96 /// </summary>
97 public class Client
98 {
99 public static int Main(string[] args)
100 {
101 // Set up chain (usually one need to be done once)
102 Handler firstHandler = new ConcreteHandler1();
103 Handler secondHandler = new ConcreteHandler2();
104 Handler thirdHandler = new ConcreteHandler3();
105 firstHandler.SetSuccessor(secondHandler);
106 secondHandler.SetSuccessor(thirdHandler);
107
108 // After setting up the chain of responsibility, we can
109 // now generate requests and pass then off to the
110 // chain to be handled
111
112 // generate and fire request
113 Request newRequest = new Request(2,"This are the request parameters");
114 firstHandler.HandleRequest(newRequest);
115
116 return 0;
117 }
118 }
