赋值运算符重载

重载赋值运算符（=），用于创建一个对象，比如拷贝构造函数。

/***
evaluate.cpp
***/
#include<iostream>
using namespace std;class Distance
{private:int feet;int inches;public:Distance(){feet = 0;inches = 0;}Distance(int f,int i){feet = f;inches = i;}void displayDistance(){cout << "F: " << feet << " I: " << inches << endl; }Distance operator=(const Distance &D){feet = D.feet;inches = D.inches;}
};int main()
{Distance D1(11,10), D2(5,11);cout << "First Distance : ";D1.displayDistance();cout << "Second Distance : ";D2.displayDistance();D1 = D2;cout << "First Distance : ";D1.displayDistance();return 0;
}

运行结果：

exbot@ubuntu:~/wangqinghe/C++/20190809$ g++ evaluate.cpp -o evaluate

exbot@ubuntu:~/wangqinghe/C++/20190809$ ./evaluate

First Distance : F: 11 I: 10

Second Distance : F: 5 I: 11

First Distance : F: 5 I: 11