第十七章 特殊成员_类的函数指针 简单

#include <iostream>
using namespace std;
class Human
{
public:
		virtual void run()=0;
	    virtual void eat()=0;
};

class Month:public Human
{
public:
	void run(){ cout<<"母亲跑百米要二十少"<<endl;}
	void eat(){ cout<<"母亲喜欢吃零食"<<endl;}
};

class Father:public Human
{
public:
	void run(){ cout<<"父亲跑百米要三十少"<<endl;}
	void eat(){ cout<<"父亲不喜欢吃零食"<<endl;}
};

class Uncle:public Human
{
public:
	void run(){ cout<<"舅舅跑百米要十五少"<<endl;}
	void eat(){ cout<<"舅舅吃零食"<<endl;}
};


int main()
{
   void (Human::*pf)()=0;
   Human *p =0;
   char choice1, choice2;
   bool quit = false;
   while(quit == false)
   {
        cout<<"(0)退出 (1)母亲 (2)父亲 (3)舅舅"<<endl;
		cin>>choice1;
		switch(choice1)
		{
		case '0':
			 quit=true;
			 break;
		case '1':
			 p = new Month;
			 break;
		case '2':
			 p = new Father;
			 break;
		case '3':
			 p = new Uncle;
			 break;
		default:
			 choice1='q';
			 break;
		}
		if(quit)
		{
		     break;
		}
		if(choice1=='q')
		{
		     cout<<"请输入0到3之间的数字"<<endl;
			 continue;
		}
		cout<<"(1)跑步 (2)进食"<<endl;
		cin>>choice2;
		switch(choice2)
		{
			case '1':
				pf=&Human::run;
				break;
			case '2':
				pf = &Human::eat;
				break;
			default:
				continue;
		}
		//p指向的是一个类
		//pf是指向一个类的函数指针
		(p->*pf)();
		 delete p;
   }
   return 0;
}