日期类

/******************************************************************************************Date.hpp:Copyright (c) Bit Software, Inc.(2013), All rights reserved.Purpose:声明并实现一个日期类Author:xxxCreated Time:2016-9-5*****************************************************************************************/#include <assert.h>class Date{public:Date (int year = 1900, int month = 1, int day = 1):_year(year),_month(month),_day(day){// 检查如果输入参数是非法时间，则初始化为1900-1-1assert(CheckDate());}Date (const Date& d):_year(d._year),_month(d._month),_day(d._day){}Date& operator= (const Date& d){if (this != &d){this->_year = d._year;this->_month = d._month;this->_day = d._day;}return *this;}// 检查时间是否有效bool CheckDate (){if(_year < 1900||(_month < 1 || _month > 12)||(_day < 1   || _day > DaysOfMonth(_year, _month)))return false;elsereturn true;}void Display (){cout<<_year<<"-"<<_month<<"-"<<_day<<endl<<endl;}public:// 若日期非法static int DaysOfMonth (int year, int month){assert(year >= 1900 && (month > 0 && month < 13));static int monthDays[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};int days = monthDays[month];// 闰年的二月要多一天if (month == 2&& ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))){days += 1;}return days;}public:bool operator == (const Date& d){return _year == d._year&& _month == d._month&& _day == d._day;}bool operator != (const Date& d){return !(*this == d);}bool operator > (const Date& d){return _year > d._year || (_year == d._year && _month > d._month)|| (_year == d._year && _month == d._month && _day > d._day);}/*bool operator > (const Date& d){if(_year > d._year)return true;if (_year == d._year){if (_month > d._month){return true;}if (_month == d._month){if (_day > d._day){return true;}}}return false;}*/bool operator >= (const Date& d){return *this > d || *this == d;}bool operator < (const Date& d){return !(*this >= d);}bool operator <= (const Date& d){return !(*this > d);}// 将日期转换为正确的日期void _ToCorrectDate(){// 若_day为负数，则开始校正日期while(_day <= 0){if (_month == 1){_year--;_month = 12;}else{_month--;}_day += DaysOfMonth (_year, _month);}// 若_day为负数，则开始校正日期while (_day >= DaysOfMonth(_year, _month)){_day -= DaysOfMonth (_year, _month);if (_month == 12){_year++;_month = 1;}else{_month++;}}}//// 计算一个日期加减一个天数以后的日期。//Date operator+(int day){Date d(*this);d._day += day;d._ToCorrectDate();return d;}Date operator-(int day){Date d(*this);d._day -= day;d._ToCorrectDate();return d;}Date& operator-=(int day){this->_day -= day;this->_ToCorrectDate();return *this;}Date& operator+=(int day){this->_day += day;this->_ToCorrectDate();return *this;} // 前置++const Date& operator++(){*this += 1;return *this;}// 后置++Date operator++(int){Date tmp(*this);*this += 1;return tmp;}// 前置--const Date& operator--(){*this -= 1;return *this;} // 后置--Date operator--(int){Date tmp(*this);*this -= 1;return tmp;}//// 两个日期相加没有意义// 计算两个日期相减以后的差的天数//int operator-(const Date& d){int flag = 1;Date min = *this, max = d;if (min < max){flag = -1;min = d;max = *this;}int gapDays = 0;while (min != max){++max;gapDays++;}return gapDays*flag;}friend istream& operator>>(istream& in, Date& d);friend ostream& operator<<(ostream& out, Date& d);private:int _year;int _month;int _day;};istream& operator>>(istream& in, Date& d){cout<<"请依次输入日期的年-月-日:"<<endl;in>>d._year>>d._month>>d._day;return in;}ostream& operator<<(ostream& out, Date& d){out<<d._year<<"-"<<d._month<<"-"<<d._day;return out;}void Test1(){Date d1(2015, 12, 15);cout<<d1<<endl;d1 += 15;cout<<d1<<endl;d1 -= 30;cout<<d1<<endl;}void PromptInfo(){cout<<"==============日期计算器================"<<endl;cout<<"1.推后几天的日期"<<endl;cout<<"2.计算日期差"<<endl;cout<<"0.退出"<<endl;cout<<"========================================"<<endl;}//// 实现日期计算器// http://bjtime.cn/riqi.asp//void TestDate(){Date d1, d2;int option, days;do {PromptInfo();cin>>option;switch(option){case 0:break;case 1:cin>>d1;if (!d1.CheckDate()){cout<<"输入日期非法！"<<endl;break;}cout<<"请出入计算推后的天数"<<endl;cin>>days;d1+=days;cout<<d1<<endl;break;case 2:cin>>d1;if (!d1.CheckDate()){cout<<"输入日期非法！"<<endl;break;}cin>>d2;if (!d2.CheckDate()){cout<<"输入日期非法！"<<endl;break;}days = d1 - d2;cout<<"相差的天数:"<<days<<endl;break;default:cout<<"选项错误，请重新选择"<<endl;break;}}while(option != 0);}