简单工厂模式

  1 // 简单工厂模式.cpp : 定义控制台应用程序的入口点。
  2 //
  3 
  4 #include "stdafx.h"
  5 #include <iostream>
  6 #include<string>
  7 using namespace std;
  8 
  9 //抽象产品
 10 class fruit
 11 {
 12 public:
 13     fruit();
 14     virtual ~fruit();
 15     //由于此类是抽象类，没有价格，所以只能将价格显示定义为纯虚函数
 16     virtual void show_price()=0;
 17 };
 18 fruit::fruit()
 19 {}
 20 fruit::~fruit()
 21 {}
 22 
 23 //具体产品1
 24 class apple :public fruit
 25 {
 26 public :
 27     apple();
 28     virtual ~apple();
 29     virtual void show_price();
 30 };
 31 apple::apple()
 32 {
 33     cout<<"i am an apple"<<endl;
 34 }
 35 apple::~apple()
 36 {}
 37 void apple::show_price()
 38 {
 39     cout<<"my price is 5"<<endl;
 40 }
 41 
 42 //具体产品2
 43 class orange :public fruit
 44 {
 45 public :
 46     orange();
 47     virtual ~orange();
 48     virtual void show_price();
 49 };
 50 orange::orange()
 51 {
 52     cout<<"i am an orange"<<endl;
 53 }
 54 orange::~orange()
 55 {}
 56 void orange::show_price()
 57 {
 58     cout<<"my price is 6"<<endl;
 59 }
 60 //简单工厂
 61 //输入要创建实例的编号，创建对应实例，1：apple，2：orange
 62 class fruit_samplefactory
 63 {
 64 public:
 65     fruit_samplefactory();
 66     ~fruit_samplefactory();
 67 public:
 68     //此处一定要声明为静态成员函数，因为非静态成员，必须首先实例化一个类对象，才能使用
 69     static fruit* creat_fruit(int name_num);
 70     //fruit* creat_fruit(int name_num);
 71 };
 72 fruit_samplefactory::fruit_samplefactory()
 73 {
 74 
 75 }
 76 fruit_samplefactory::~fruit_samplefactory()
 77 {
 78 
 79 }
 80 fruit* fruit_samplefactory::creat_fruit(int name_num)
 81 {
 82     switch(name_num)
 83     {
 84     case 1:
 85             return new apple;
 86             break;
 87     case 2:
 88             return new orange;
 89             break;
 90     default:
 91         cout<<"您输入的类型不存在"<<endl;
 92         return NULL;
 93         break;
 94     }
 95 }
 96 
 97 //用户界面
 98 int _tmain(int argc, _TCHAR* argv[])
 99 {
100     int num=2;
101     fruit* orange=NULL;
102     orange=fruit_samplefactory::creat_fruit(num);
103     orange->show_price();
104     delete orange;
105     orange=NULL;
106     return 0;
107 }