C++ 重载运算符 operator

妖狐艹你老母 2022-09-04 02:42 180阅读 0赞

## operator  是什么 ##

operator 是C++的一个关键字，它和运算符（+,-,\*,/,=,等等）一起使用，表示一个运算符重载函数

operator 没有返回语句

## operator 的作用 : ##

### 1 把对象当函数使用 ###

具体的如下:

#include <iostream>
    #include <string>
    using namespace std;
    class People
    {
    public:
        // 把对象当函数使用
        int operator()(int a, int b) const
        {
            return a + b;
        }
    };
    
    int main()
    {
        People p;
        cout << p(13, 15) << endl;
        return 0;
    }

### 2 对象进行计算 ###

operator的操作符有很多,如下

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzMzMjEwMDQy_size_16_color_FFFFFF_t_70][]

具体代码如下:

#include <iostream>
    #include <string>
    using namespace std;
    
    class People
    {
    
    public:
        int mage;
    
    public:
        People(int age)
        {
            mage = age;
        }
    
        People operator+(People p)
        {
            return People(mage + p.mage);
        }
    
        void showMessage()
        {
            cout << mage << endl;
        }
    };
    
    int main()
    {
        People people1(18);
        People people2(20);
        People people3(0);
        people3 = people1 + people2;
        people3.showMessage();
        return 0;
    }

###  3 类型转换 ###

#include <iostream>
    #include <string>
    using namespace std;
    
    class People
    {
    
    public:
        int height;
    
    public:
        People(double mheight =0){
            height  = mheight;
        };
        
       operator double()
        {
            return height;
        }
    
    };
    
    
    int main()
    {
        People people1(175.5);
        People people2(180.3);
        People people3(0);
        people3 = people1 + people2;
        cout<<people3<<endl;
        return 0;
    }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzMzMjEwMDQy_size_16_color_FFFFFF_t_70]: /images/20220829/d05ed21b680e4098987b759be1090de0.png