简单工厂模式

 1 #define win 0
 2 #define mac 1
 3 #include <iostream>
 4 using namespace std;
 5 
 6 class button     //抽象基类   类似于接口 
 7 {
 8 public:
 9     button(){}
10     virtual void createbutton()=0;
11 };
12 
13 class macbutton : public button
14 {
15 public:
16     macbutton(){}
17     virtual void createbutton(){cout<<"macbutton"<<endl;}
18 };
19 class winbutton : public button
20 {
21 public:
22  winbutton(){}
23  virtual void createbutton(){cout<<"winbutton"<<endl;}
24 };
25 
26 class simplefactory
27 {
28 public:
29     simplefactory(){}
30     button *createproduct(int ID);    //返回值是抽象基类的指针 
31     button *createmacproduct();
32     button *createwinproduct();
33 };
34 
35 button *simplefactory::createproduct(int ID)
36 {
37     if (ID==win)
38         return new winbutton;       //直接返回new<T> 
39     if (ID==mac)
40         return new macbutton;
41 }
42 
43 button *simplefactory::createwinproduct()
44 {
45     return new winbutton;
46 }
47 
48 button *simplefactory::createmacproduct()
49 {
50     return new macbutton;
51 }
52 
53 int main()
54 {
55     simplefactory fc;    //声明或创建一个工厂 
56     button *bt=fc.createproduct(win);   //用工厂生产 生产是个指针 
57     bt->createbutton();
58     delete bt;
59     return 0;
60 }