类型转换操作符函数

#include "stdafx.h"#include <iostream>using namespace std;#include <string>//用类型转换操作符函数进行转换(在自己的类中实现)class Point2D{public:Point2D(int x, int y):_x(x), _y(y){}void dis(){cout << "(" << _x << "," << _y << ")"<< endl;}Point2D &operator=(const Point2D &another){this->_x = another._x;this->_y = another._y;return *this;}private:int _x;int _y;};class Point3D{public:Point3D(int x, int y, int z):_x(x), _y(y), _z(z){}void dis(){cout << "(" << _x << "," << _y << "," << _z << ")"<< endl;}//无参，无返回operator Point2D(void){return Point2D(this->_x, this->_y);}private:int _x;int _y;int _z;};int _tmain(int argc, _TCHAR* argv[]){Point3D p3(1, 2, 3);Point2D p2(0, 0);p2 = p3; //先调用的无参无返回的函数 然后在函数中//调用Point2D的构造器,最后运算符重载(可用默认)p2.dis();return 0;}