神奇！居然能访问私有成员，求教，谢谢

csdaa2010 2014-04-05 07:18:00

今天在写一个复数计算程序时，居然发现能访问私有成员,神奇
在谷歌上搜索无果后，贴出来希望高手能赐教
谢谢

VC6.0下调试的



//ComplexH.h

#ifndef Complex_H

#define Complex_H/*注意这个宏定义不要和类名相同*/

class Complex

{

	private:

		float real;

		float image;

	public:

		Complex();										//构造函数

		Complex(float real,float image);				//构造函数

		Complex(const Complex &c);						//构造函数(拷贝)

		Complex & operator =(const Complex &c);			//重载等符号

		Complex operator +(const Complex &c)const;		//重载等符号

		Complex operator -(const Complex &c)const;		//重载等符号	

		Complex operator *(const Complex &c)const;		//重载等符号

		Complex operator /(const Complex &c)const;		//重载等符号

		friend void display(const Complex &c);			//显示内容(友元)

		friend float GetReal(const Complex &c);			//获取实数部分(友元)			

		friend float GetImage(const Complex &c);		//获取虚数部分(友元)

		friend void  SetReal(Complex &c,const float n);	//设置实数部分(友元)				

		friend void  SetImage(Complex &c,const float n);//设置虚数部分(友元)				

		~Complex();										//析构函数

};

#endif



//Complex.cpp

#include "ComplexH.h"

#include <iostream>

using std::cin;

using std::cout;

using std::endl;

/*

		Complex();										//构造函数

		Complex(float real,float image);				//构造函数

		Complex(const Complex &c);						//构造函数(拷贝)

		Complex & operator =(const Complex &c);			//重载等符号

		Complex operator +(const Complex &c)const;		//重载等符号

		Complex operator -(const Complex &c)const;		//重载等符号	

		Complex operator *(const Complex &c)const;		//重载等符号

		Complex operator /(const Complex &c)const;		//重载等符号

		friend void display();							//显示内容(友元)

		friend float GetReal(const Complex &c);			//获取实数部分(友元)			

		friend float GetImage(const Complex &c);		//获取虚数部分(友元)

		friend void  SetReal(Complex &c,const float n);	//设置实数部分(友元)				

		friend void  SetImage(Complex &c,const float n);//设置虚数部分(友元)				

		~Complex();										//析构函数

*/

Complex::Complex()

{

	this->image = 0;

	this->real = 0;

	cout<<"使用无参构造函数"

		<<endl;

}

Complex::Complex(float real,float image)

{

	this->real  = real;

	this->image = image;

	cout<<"使用两个参数的构造函数"

		<<"real:"<<real<<" , "

		<<"image:"<<image

		<<endl;

}

Complex::Complex(const Complex &c)

{

	this->image = c.image;

	this->real = c.real;

	cout<<"拷贝函数启动"<<endl;

}

Complex::~Complex()

{

	cout<<"析构函数启动!"

		<<endl;

}

Complex Complex::operator +(const Complex &c)const

{

	

	return (*new Complex(c.real + this->real,c.image + this->image));//神奇，为什么能访问C的私有成员????

}

Complex Complex::operator -(const Complex &c)const/*如果是a-b,b-a怎么区分?*/

{

	return (* new Complex(this->real-c.real,this->image-c.image));

}

Complex Complex::operator *(const Complex &c)const

{

	return (*new Complex(this->real*c.real-this->image*c.image,this->real*c.image+this->image*c.real));

}

Complex Complex::operator /(const Complex &c)const

{

	float t = c.real * c.real + c.image * c.image;

	float r,i;

	if(!t)

	{

		cout<<"不能被0除"<<endl;

		exit(-1);

	}

	r = this->real * c.real + this->image * c.image;

	i = this->image*c.real - c.image*this->real;

	return (Complex(r/t,i/t));

}

Complex& Complex::operator =(const Complex &c)/*注意此处!!!!!!!*/

{

	if(this==&c)

		return *this;

	return (* new Complex(c.real,c.image));

}

float GetReal(const Complex &c)

{

	return c.real;

}

float GetImage(const Complex &c)

{

	return c.image;

}

void SetReal(Complex &c,const float n)

{

	c.real = n;

}

void SetImage(Complex &c,const float n)

{

	c.image = n;

}

void SetComplex(Complex &c,float real,float image)

{

	SetReal(c,real);

	SetImage(c,image);

}

void display(const Complex &c)

{

	cout<<"display():"

		<<c.real

		<<" , "

		<<c.image<<"i"

		<<endl;

}



//Enter.cpp

#include <iostream>

#include "Complex.cpp"

using std::cin;

using std::cout;

using std::endl;

int main()

{

	cout<<"****************初始化****************"<<endl;

	Complex comp_a,comp_b(2,3);

	cout<<"comp_a:";

	display(comp_a);

	cout<<"comp_b:";

	display(comp_b);

	cout<<"****************初始化****************"<<endl<<endl;



	cout<<"****************修改****************"<<endl;

	SetComplex(comp_a,1,1);

	cout<<"修改comp_a为：1,1\n \bcomp_a:";

	display(comp_a);

	cout<<"****************修改后****************"<<endl<<endl;



	cout<<"****************相加****************"<<endl;

	cout<<"两数【相加】"<<endl;

	display(comp_a+comp_b);

	cout<<"****************相加****************"<<endl<<endl;

	

	return 0;

}