date.cpp

标准C++编写的小小CRM软件,无任何平台依赖.采用标准XML作为数据库.只需重新纺译,可在任何平台上运行.目前测试过在GCC和VC下都可以编译通过

// Date.cpp: implementation of the Date class.
//
//////////////////////////////////////////////////////////////////////

#include "Date.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

// Initialize staitc member at file scope.
const unsigned Date::days[] = { 0, 31, 28, 31, 30, 31, 30, 
						  31, 31, 30, 31, 30, 31, };
Date::Date():year(1),month(1),day(1)
{}

Date::Date(unsigned y,unsigned m,unsigned d)
{	setDate( y, m, d );		}

Date::Date( const Date& date )
{	setDate( date.year, date.month, date.day );	}

Date::Date( char* date )
{
	char ch;
	unsigned y,m,d;
	istrstream tStream(date);

	tStream>>y>>ch>>m>>ch>>d;
	setDate( y, m, d );
}

void Date::setDate( unsigned y, unsigned m, unsigned d )
{
	month = ( m>=1 && m<=12 ) ? m : 1;
	year = ( y<100000 ) ? y : 2000;

	if( 2 == month && leapYear( year ) )
	{	day = ( d >= 1 && d <= 29 ) ? d : 1;	}
	else
	{	day = ( d >= 1 && d <= days[ month ] ) ? d : 1;	}
}


Date::~Date()
{}

bool Date::leapYear( int y ) const
/* If the year is a leap year, return true, else return false		*/
{
	if( 0 == y % 400 || ( 0 != y % 100 && 0 == y % 4 ) )
	{	return true;	}		// a leap year
	else
	{	return false;	}
}

bool Date::endOfMonth( int d ) const
/* if the day is the end of month return true, else return false	*/
{ 
	if( month == 2 && leapYear( year ) )
	{	return 29 == d;				}	// last day of Feb in leap year
	else
	{	return days[ month ] == d;	}
}

void Date::increment( )
/* increment one day. */
{
	if( endOfMonth( day ) && 12 == month ){	// end year
		day = 1;
		month = 1;
		++year;
	}
	else if( endOfMonth( day ) ){		// end month
		day = 1;
		++month;
	}
	else
	{	++day;	}
}

Date& Date::operator ++ ()
/* increamet one day */
{
	increment();

	/* return non-incremented, saved, temporary object. */
	return *this;	// value return, not a reference return
}

const Date& Date::operator += ( unsigned d )
/* add a specific number of days to a date.	*/
{
	for( unsigned i = 0; i < d; i++ )
	{	increment();	}

	return *this;	// enables cascading
}

bool Date::operator==(const Date& date)
/* If two date all the same then return true, else return false.*/
{	return day==date.day && month==date.month && year==date.year;	}

bool Date::operator>(const Date& date)
/* If the first date later than the follow, return true			*
 * else return false.											*/
{
	return year>date.year 
		|| year==date.year && month>date.month
		|| month==date.month && day>date.day;
}


bool Date::operator < (const Date& date)
/* If the first date earlier than the follow, return true	*
 * else return false.											*/
{
	return year<date.year 
		|| year==date.year && month<date.month
		|| month==date.month && day<date.day;
}

istream& operator>> ( istream& is, Date& date)
{	
	char ch;
	unsigned y, m, d;
	is >> y >> ch >> m >> ch >> d;
	date.setDate( y, m, d );

	return is;
}

ostream& operator << ( ostream& os, Date& date)
{
	os << date.year << '-' << date.month << '-' << date.day;
	return os;
}