【Linux基础】运算符重载为类的友元函数

类中的声明：

friend 函数类型 operator 运算符（参数表）；

运算符重载函数的定义形式：

函数类型 operator 运算符（参数表）

{

函数体；

}

例5 用友元函数实现复数类加减运算符的重载

#include "iostream.h"

class CComplex

{

private:

double real;

double imag;

public:

CComplex(double r=0, double i=0);

void Print();

friend CComplex operator +(CComplex c1,CComplex c2);

friend CComplex operator -(CComplex c1,CComplex c2);

};

CComplex::CComplex (double r, double i)

{

real = r;

imag = i;

}

void CComplex:rint()

{

cout << "(" << real << "," << imag << ")" << endl;

}

CComplex operator +(CComplex c1, CComplex c2)

{

CComplex temp;

temp.real = c1.real + c2.real;

temp.imag = c1.imag + c2.imag;

return temp;

}

CComplex operator -(CComplex c1, CComplex c2)

{

CComplex temp;

temp.real = c1.real - c2.real;

temp.imag = c1.imag - c2.imag;

return temp;

}

void main(void)

{

CComplex a(1, 2), b(3.0, 4.0), c, d, e;

c = a+b;

相当于函数调用“c=operator+(a, b)”

d = b-10;

e = 20+a;

cout << "c = ";

c.Print();

cout << "d = ";

d.Print();

cout << "e = ";

e.Print();

}

程序运行结果为：

c = （4, 6）

d = （-7, 4）

e = （21, 2）

本文转载于唯C教育，【Linux基础】运算符重载为类的友元函数
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