访问者模式

 1 #include <iostream>
 2 #include <list>
 3 #include <string>
 4 using namespace std;
 5  
 6 class Person
 7 {
 8 public:
 9     string action;
10     virtual void getConclusion() = 0;
11 };
12 
13 class Man:public Person
14 {
15 public:
16     void getConclusion()
17     {
18         if (action == "成功")
19         {
20             cout << "男人成功时，背后多半有一个伟大的女人。" << endl;
21         }
22         else if (action == "恋爱")
23         {
24             cout << "男人恋爱时，凡事不懂装懂。" << endl;
25         }        
26     }
27 };
28 
29 class Woman : public Person
30 {
31 public:
32     void getConclusion()
33     {
34         if (action == "成功")
35         {
36             cout << "女人成功时，背后多半有失败的男人。" << endl;
37         }
38         else if (action == "恋爱")
39         {
40             cout << "男人恋爱时，遇到事懂也装不懂。" << endl;
41         }        
42     }
43 };
44 
45 int main()
46 {
47     list<Person*> persons;
48 
49     Person *man1 = new Man();
50     man1->action = "成功";
51     persons.push_back(man1);
52      
53     Person *woman1 = new Woman();
54     woman1->action = "成功";
55     persons.push_back(woman1);
56 
57     Person *man2 = new Man();
58     man2->action = "恋爱";
59     persons.push_back(man2);
60 
61     Person *woman2 = new Woman();
62     woman2->action = "恋爱";
63     persons.push_back(woman2);
64 
65     list<Person*>::iterator iter = persons.begin();
66     while (iter != persons.end())
67     {
68         (*iter)->getConclusion();
69         ++iter;
70     }
71     return 0;
72 }
73 //Result:
74 /*
75 男人成功时，背后多半有一个伟大的女人。
76 女人成功时，背后多半有失败的男人。
77 男人恋爱时，凡事不懂装懂。
78 男人恋爱时，遇到事懂也装不懂。
79 */