Classic observer mode example)

Recently, when browsing in the garden, many of my friends are reading a classic C # interview question:
"The Cat is called, the mouse is running, and the host is awakened". C # is required.
Many friends in the garden have already implemented it. The specific method is implemented through the observer mode or event.
Here I will first extract the implementation of the observer mode, Code As follows: 1 Namespace Nickname
2 {
3 // The mouse ran and the host woke up.
4 // Use observer Mode
5 // Step 1 abstract observer
6 Public   Interface Observer
7 {
8 Void Response (); // Respond after receiving the event
9 }
10 // Step 2 Abstract The main object (CAT) that triggers the observer's response)
11 Public   Interface Subject
12 {
13 Void Aimat (Observer ob ); // The target object that will be used after the call
14 }
15 // Abstract mice and masters
16 Public   Class Mouse: Observer
17 {
18 Private   String Name;
19 Public Mouse ( String Name, subject sub) // Add observation on the subject object to the constructor (here we will observe the cat)
20 {
21 This . Name = Name;
22 Sub. aimat ( This );
23 }
24 Public   Void Response ()
25 {
26 Console. writeline ( " Cat cryed, "   + Name +   " Run! " );
27 }
28 }
29 Public   Class MASTER: Observer
30 {
31 Private   String Name;
32 Public Master ( String Name, subject sub) // Add observation on the subject object to the constructor (here we will observe the cat)
33 {
34 This . Name = Name;
35 Sub. aimat ( This );
36 }
37 Public   Void Response ()
38 {
39 Console. writeline ( " Cat cryed, "   + Name +   " Is weakup! " );
40 }
41 }
42 Public   Class Cat: Subject
43 {
44 Private List < Observer > Obs;
45 Public CAT ()
46 {
47 This . Obs =   New List < Observer > ();
48 }
49 Public   Void Aimat (Observer ob)
50 {
51 This . Obs. Add (OB );
52 }
53 Public   Void Cry ()
54 {
55 Foreach (Observer ob In   This . Obs)
56 {
57 Ob. Response ();
58 }
59 }
60 }
61 Class Program
62 {
63 Static   Void Main ( String [] ARGs)
64 {
65 Cat = New CAT ();
66 Mouse mouse1 =   New Mouse ( " Mouse1 " , CAT );
67 Mouse mouse2 =   New Mouse ( " Mouse2 " , CAT );
68 Master =   New Master ( " Xu " , CAT );
69 Cat. Cry ();
70 Console. Readline ();
71 }
72 }
73 }
Abstract ---- the essence of all design patterns.