日期类的实现---代码部分

1.头文件（Date.h）

#define _CRT_SECURE_NO_WARNINGS 1

#include<iostream>
#include<assert.h>
using namespace std;

class Date{
	friend ostream& operator<<(ostream& out, const Date& d);
	friend istream& operator>>(istream& in, Date& d);
public:
	Date(int year = 2024, int month = 1, int day = 1);
	void Print();

	bool CheckDate()
	{
		if (_month < 1 || _month > 12
			|| _day < 1 || _day > GetMonthDay(_year, _month))
		{
			return false;
		}
		else
		{
			return true;
		}
	}

	int GetMonthDay(int year, int month) const
	{
		assert(month > 0 || month < 13);
		static int MonthDayArray[13] = { -1,31,28,31,30,31,30,31,31,30,31,30,31 };

		if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)))
		{
			return 29;
		}

		return MonthDayArray[month];
	}

	bool operator<(const Date& d);
	bool operator>(const Date& d);
	bool operator<=(const Date& d);
	bool operator>=(const Date& d);
	bool operator==(const Date& d);
	bool operator!=(const Date& d);
	
	Date& operator+=(int day);
	Date operator+(int day);

	Date& operator-=(int day);
	Date operator-(int day);

	//++d
	Date& operator++();
	//d++
	Date operator++(int);

	//--d
	Date& operator--();
	//d--
	Date operator--(int);

	int operator-(const Date& d);

private:
	int _year;
	int _month;
	int _day;
};

ostream& operator<<(ostream& out, const Date& d);
istream& operator>>(istream& in, Date& d);

2.源文件（Date.cpp）

#define _CRT_SECURE_NO_WARNINGS 1

#include"project.h"

Date::Date(int year, int month, int day)
{
	_year = year;
	_month = month;
	_day = day;

	if (!CheckDate())
	{
		cout << "日期非法->";
		cout << *this << endl;
	}
}

void Date::Print()
{
	cout << _year << "-" << _month << "-" << _day << endl;
}

bool Date::operator<(const Date& d)
{
	if (_year < d._year)
	{
		return true;
	}
	else if (_year == d._year
		&& _month < d._month)
	{
		return true;
	}
	else if (_year == d._year
		&& _month == d._month
		&& _day < d._day)
	{
		return true;
	}
	return false;
}

bool Date::operator>(const Date& d)
{
	return !(*this <= d);
}

bool Date::operator<=(const Date& d)
{
	return *this < d || *this == d;
}

bool Date::operator>=(const Date& d)
{
	return !(*this < d);
}

bool Date::operator==(const Date& d)
{
	return _year == d._year
		&& _month == d._month
		&& _day == d._day;
}

bool Date::operator!=(const Date& d)
{
	return !(*this == d);
}

Date& Date::operator+=(int day)
{
	if (day < 0)
	{
		return *this -= -day;
	}

	_day += day;
	while (_day > GetMonthDay(_year, _month))
	{
		_day -= GetMonthDay(_year, _month);
		++_month;
		if (_month == 13)
		{
			_year++;
			_month = 1;
		}
	}
	return *this;
}

Date Date::operator+(int day)
{
	Date tmp = *this;
	tmp += day;
	return tmp;
}

Date& Date :: operator-=(int day)
{
	if (day < 0)
	{
		return *this += -day;
	}
	_day -= day;
	while (_day <= 0)
	{
		--_month;
		if (_month == 0)
		{
			_month = 12;
			--_year;
		}
		_day += GetMonthDay(_year, _month);
	}
	return *this;
}

Date Date::operator-(int day)
{
	Date tmp(*this);
	tmp -= day;
	return tmp;
}

Date& Date::operator++()
{
	*this += 1;
	return *this;
}

Date Date::operator++(int)
{
	Date tmp(*this);
	*this += 1;
	return tmp;
}

Date& Date::operator--()
{
	return *this -= 1;
}

Date Date::operator--(int)
{
	Date temp = *this;
	*this -= 1;
	return temp;
}

int Date::operator-(const Date& d)
{
	Date max = *this;
	Date min = d;
	int flag = 1;
	if (*this < d)
	{
		max = d;
		min = *this;
		flag = -1;
	}

	int n = 0;
	while (min != max)
	{
		++min;
		++n;
	}

	return n * flag;
}

ostream& operator<< (ostream& out, const Date& d)
{
	cout << d._year << "年" << d._month << "月" << d._day << "日" << endl;
	return out;
}

istream& operator>>(istream& in, Date& d)
{
	while (1)
	{
		cout << "请输入年月日：";
		in >> d._year >> d._month >> d._day;
		if (d.CheckDate())
		{
			break;
		}
		else
		{
			cout << "日期非法，重新输入" << endl;
		}
	}
	return in;
}

3.测试文件（Test.cpp）—个人测试，仅供参考

#define _CRT_SECURE_NO_WARNINGS 1
#include"project.h"

//int main()
//{
//	Date d1(2024, 8, 10);
//	d1.Print();
//
//	//Date d2(d1 + 100);
//	Date d2 = d1 + 100;
//	d2.Print();
//	d1.Print();
//
//	d1 += 100;
//	d1.Print();
//
//	int i = 1;
//	i += 100;
//
//	d1 -= 100;
//	d1.Print();
//
//	cout << endl;
//
//	Date d3(2024, 8, 10);
//	d3.Print();
//	d3 += 7000;
//	d3.Print();
//
//	return 0;
//}

//int main()
//{
//	Date d1(2024, 8, 10);
//	d1.Print();
//
//	d1 += 100;
//	d1.Print();
//
//	d1 += -100;
//	d1.Print();
//
//	Date ret1 = ++d1;
//	d1.Print();
//
//	Date ret2 = d1++;
//	d1.Print();
//
//	ret1.Print();
//	ret2.Print();
//
//	return 0;
//}

// 17:20
int main()
{
	Date d1(2024, 8, 10);
	Date d2(2004, 2, 5);

	cout << d1 - d2 << endl;
	cout << d2 - d1 << endl;

	//d1 << cout;
	//d1.operator<<(cout);

	Date d(2023, 2, 29);

	cout << d1;
	operator<<(cout, d1);

	cin >> d1 >> d2;
	cout << d1 << d2 << endl;



	return 0;
}