3-24.txt

思路很清晰的c++课件。例子很简明

例3.24 使用友元成员函数访问另一个类

#include <iostream.h>
#include <string.h>
class girl;			//向前引用
class boy{
	char *name;
	int age;
public:
	boy(char *N,int A)
	{	name=new char[strlen(N)+1];
		strcpy(name,N);
		age=A;
	}
	void disp(girl &);	//声明disp()为类boy的成员函数
	~boy(){delete name;}
}; 
class girl{
	char *name;
	int age;
public:
	girl(char *N,int A)
	{	name=new char[strlen(N)+1];
		strcpy(name,N);
		age=A;
	}
	friend void boy::disp(girl &);	//声明类boy的成员函数disp()为类girl的友元函数
	~girl(){delete name;}
};

void boy::disp(girl &x)
{	cout<<"boy\'s name is:"<<name<<",age:"<<age<<endl;  //访问本类对象成员
	cout<<"girl\'s name is:"<<x.name<<",age:"<<x.age<<endl;  //访问友元类对象成员
}
void main()
{	boy b("chen hao",25);
	girl g("zhang wei",18);
	b.disp(g);
}