How to use operator overloading in C++

这篇文章主要介绍C++中运算符重载怎么用，文中介绍的非常详细，具有一定的参考价值，感兴趣的小伙伴们一定要看完!

运算符重载

为什么要使用运算符重载

-C/C++的运算符，支持的数据类型，仅限于基本数据类型。

问题：一头牛+一头马 = ？（牛马神兽？）

一个圆 +一个圆 = ？ （想要变成一个更大的圆）

一头牛 – 一只羊 = ？ (想要变成4只羊，原始的以物易物：1头牛价值5只羊)

解决方案：

使用运算符重载

方式一, 使用成员函数重载运算符 需求：把牛肉换猪肉, 羊肉换猪肉

规则：

一斤牛肉：2斤猪肉

一斤羊肉：3斤猪肉

实现:

牛 + 牛 = ?猪肉

牛 + 羊 = ?猪肉

Cow类

> Cow.h#pragma onceclass Pork;class Sheep; class Cow{ //牛类public: Cow(int weight = 0); //使用运算符重载, 实现 牛肉 + 牛肉 = 猪肉 Pork operator+(const Cow& cow); //使用运算符重载, 实现 牛肉 + 羊肉 = 猪肉 Pork operator+(const Sheep& sheep);private: int weight; //重量};_________________________________________________________________________________________________________________________________> Cow.cpp#include "Cow.h"#include "Pork.h"#include "Sheep.h"Cow::Cow(int weight){ this->weight = weight;}//一斤牛肉换两斤猪肉Pork Cow::operator+(const Cow& cow){ return Pork((this->weight + cow.weight) * 2);}//一斤牛肉换两斤猪肉, 一斤羊肉换三斤猪肉Pork Cow::operator+(const Sheep& sheep){ int tmp = (this->weight * 2) + (sheep.getWeight() * 3); return Pork(tmp);}

Sheep类

> Sheep.h#pragma once//羊类class Sheep{public: Sheep(int weight = 0); int getWeight() const;private: int weight; //重量};_________________________________________________________________________________________________________________________________> Sheep.cpp#include "Sheep.h"Sheep::Sheep(int weight){ this->weight = weight;}int Sheep::getWeight() const{ return weight;}

Pork类

> Pork.h#pragma once#include using namespace std;class Pork{ //猪肉类public: Pork(int weight = 0); string description() const;private: int weight;};_________________________________________________________________________________________________________________________________> Pork.cpp#include #include "Pork.h"Pork::Pork(int weight){ this->weight = weight;}string Pork::description() const{ stringstream ret; ret weight Pork.h#pragma once#include using namespace std;class Pork{ //猪肉类public: Pork(int weight = 0); string description() const;private: int weight;};_________________________________________________________________________________________________________________________________> Pork.cpp#include #include "Pork.h"Pork::Pork(int weight){ this->weight = weight;}string Pork::description() const{ stringstream ret; ret weight