OperatorOverlod

原创于 2010-10-21 11:27:00 发布 · 230 阅读

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CC 4.0 BY-SA版权

本文通过一个C++程序实例介绍了操作符重载的基本用法，包括加法操作符+和插入操作符<<的重载实现。通过定义Time类来演示如何使自定义类型能够使用这些操作符。

Code:

// operatorrOverlode.cpp
/*练习使用操作符的重载特性
有+，<<的重载*/
#include <iostream>
using namespace std;
class Time;
ostream & operator<< (ostream &os,const Time &T);//友元函数须全局申明！！
class Time{
private:
int hour;
int minute;
public:
Time();//构造0hours,0minutes
Time(int h, int m);//构造用户要求的时间
void addHour(int h);//加小时
void addMin(int m);//加分钟
void reSet(int h, int m);//重置
Time operator+ (Time &T);//两个Time对象相加,重载
friend ostream & operator<< (ostream &os,const Time &T);
};
Time::Time(){
hour = 0;
minute = 0;
}//构造0hours,0minutes
Time::Time(int h, int m){
hour = h;
minute = m;
}//构造用户要求的时间
void Time::addHour(int h){
hour += h;
}//加小时
void Time::addMin(int m){
minute += m;
hour += minute / 60;
minute %= 60;
}//加分钟
void Time::reSet(int h, int m){
hour = h;
minute = m;
}//重置
Time Time::operator+ (Time &T){
Time sum;
sum.minute = T.minute + minute;
sum.hour = T.hour + hour + sum.minute / 60;
sum.minute %= 60;
return sum;
}//两个Time对象相加,重载
ostream & operator<< (ostream &os,const Time &T){
os << T.hour << " hours," << T.minute << " minutes.";
return os;
}
void main()
{
Time planning;
Time coding(2,40);
Time fixing(5,55);
Time total;
cout << "Planning time = " << planning << endl;
cout << "Coding time = " << coding << endl;
cout << "Fixing time = " << fixing << endl;
total = coding + fixing;
cout << "Coding + Fixing = " << total << endl;
cout << "Reset the time .../nCoding hours add 3,minute add 40" << endl;
coding.addHour(3);
coding.addMin(40);
cout << "Coding time = " << coding << endl;
cout << "Reser the time.../nFixing hours set4,minute ser 38" << endl;
fixing.reSet(4,38);
cout << "Fixing time = " << fixing << endl;
cout << "Coding + Fixing = " << coding + fixing << endl;
}

Code:

Planning time = 0 hours,0 minutes.
Coding time = 2 hours,40 minutes.
Fixing time = 5 hours,55 minutes.
Coding + Fixing = 8 hours,35 minutes.
Reset the time ...
Coding hours add 3,minute add 40
Coding time = 6 hours,20 minutes.
Reser the time...
Fixing hours set4,minute ser 38
Fixing time = 4 hours,38 minutes.
Coding + Fixing = 10 hours,58 minutes.
Press any key to continue