递增运算符重载

递增运算符重载

• 作用：通过重载递增运算符，实现自己的整形数据

代码示例：

#include <iostream>
using namespace std;
//重载递增运算符
//自定义整形
class MyIntegrer
{
   
       friend ostream& operator<<(ostream& cout, MyIntegrer myint);
public:
       MyIntegrer()
       {
   
              m_Num = 0;
       }
       //重载前置++运算符 返回引用是为了一直对一个数据进行递增操作
       MyIntegrer& operator++()
       {
   
              //先进行++运算符
              m_Num++;
              return *this;
       }
       //重载后置++运算符
       //void operator++(int) int 代表占位参数，可以用于区分前置和后置递增
       MyIntegrer operator++(int)
       {
   
              //先 记录当时结果
              MyIntegrer temp = *this;
              //后 递增
              m_Num++;
              //最后将记录结果做返回
              return temp;
       }
private:
       int m_Num;
};
//重载<<运算符
//
ostream& operator<<(ostream& cout, MyIntegrer myint)
{
   
       cout << myint.m_Num;
       return cout;
}
void test01()
{
   
       MyIntegrer myint;
       cout << ++(++myint) << endl;
       cout << myint << endl;
}
void test02()
{
   
       MyIntegrer myint;
       cout << myint++ << endl;
       cout << myint << endl;
}
int main()
{
   
       test01();
       int a = 0;
       cout << ++(++a) << endl;
       cout << a << endl;
       return 0;
}

总结：前置递增返回引用，后置递增返回值