C#面向对象设计模式纵横谈——20 Chain of Responsibility职责链模式
主讲：李建忠
来源：http://www.microsoft.com/china/msdn/events/webcasts/shared/webcast/consyscourse/CsharpOOD.aspx
1: abstract class BaseHandler
2: {
3: public BaseHandler(BaseHandler next)
4: {
5: this.next=next;
6: }
7:
8: protected abstract bool CanHandleRequest();
9: public abstract void HandleRequest(Request request)
10: {
11: if(this.next!=null)
12: {
13: this.next.HandleRequest(request);
14: }
15: }
16:
17: private BaseHandler next;
18:
19: public BaseHandler Next
20: {
21: get
22: {
23: return this.next;
24: }
25: set
26: {
27: this.next=value;
28: }
29: }
30: }
31:
32: public class AHandler:BaseHandler
33: {
34: public AHandler(BaseHandler next):base(next)
35: {
36:
37: }
38:
39: pprotected override bool CanHandleRequest()
40: {
41:
42: }
43:
44: public override void HandleRequest(Request request)
45: {
46: if(this.CanHandleRequest())
47: {
48:
49: }
50: else
51: {
52: base.HandleRequest(request);
53: }
54: }
55: }
56:
57: public class BHandler:BaseHandler
58: {
59: public BHandler(BaseHandler next):base(next)
60: {
61:
62: }
63:
64: pprotected override bool CanHandleRequest()
65: {
66:
67: }
68:
69: public override void HandleRequest(Request request)
70: {
71: if(this.CanHandleRequest())
72: {
73:
74: }
75: else
76: {
77: base.HandleRequest(request);
78: }
79: }
80: }
81:
82: public class CHandler:BaseHandler
83: {
84: public CHandler(BaseHandler next):base(next)
85: {
86:
87: }
88:
89: pprotected override bool CanHandleRequest()
90: {
91:
92: }
93:
94: public override void HandleRequest(Request request)
95: {
96: if(this.CanHandleRequest())
97: {
98:
99: }
100: else
101: {
102: base.HandleRequest(request);
103: }
104: }
105: }
106:
107: public class Sender
108: {
109: public void Process()
110: {
111: Request request=new Request();
112:
113: Handler handler1=new AHandler(null);
114: Handler handler2=new BHandler(handler1);
115: Handler handler3=new CHandler(handler2);
116:
117: handler3.HandleRequest(request);
118: }
119: }
