xbDate Methods

Chapter Updated 8/21/03


This chapter lists the xbDate methods and provides an example program to demonstrate usage.
Xbase .DBF files and the xbDate class handle dates in the format of CCYYMMDD (Date8).


xbDate Method List API
MethodDescription
xbDate( const char * Date8 )
xbDate( const xbString & Date8 )
xbDate() 		Class constructors. If no date provided, or invalid date provided, date is set to Sysdate().
~xbDate()Class destructor
xbString & CharDayOf( const char *Date8 )
xbString & CharDayOf( const xbString & Date8 )
xbString & CharDayOf() 		Returns Sun - Sat day of week for a given date
xbString & CharMonthOf( const char *Date8 )
xbString & CharMonthOf( const xbString & Date8 )
xbString & CharMonthOf()		Returns Jan - Dec month of year for a given date
int DateIsValid( const char *Date8 ) const
int DateIsValid( const xbString & Date8 ) const 		Checks a date for validity, returns true (1) if date is valid
int DayOf( int Format, const char *Date8 ) const
int DayOf( int Format, const xbString &Date8 ) const
int DayOf( int Format ) const		Returns day of WEEK, MONTH or YEAR from a given date where Format is one of
XB_FMT_WEEK => Number of day in week 0-6 (sun-Sat)
XB_FMT_MONTH => Number of day in month 1-31
XB_FMT_YEAR => Number of day in year 1-366
xbString & Formatdate( const char * Format, const char * Date8 )
xbString & FormatDate( const xbString & Format, const char * Date8 )
xbString & FormatDate( const char * Format, const xbString & Date8 )
xbString & FormatDate( const xbString & Format, const xbString & Date8 )
xbString & FormatDate( const xbString & Format )
xbString & FormatDate( const char * )
Return a formatted date.
Format - A format specifier with the following paramaters:
1) YYDDD - A julian date format
2) YY or YYYY will print a 2 or 4 digit year
3) M,MM,MMM or MMMM
M - one digit month if no leading zero
MM - two digit month, contains leading zero
MMM - Jan through Dec
MMMM - January through December
4) D,DD,DDD or DDDD
D - one digit dayif no leading zero
DD - two digit day, contains leading zero
DDD - Sun through Sat (or julian if YYDDD)
DDDD - Sunday through Saturday
const xbString & GetDate() const
xbString & GetDate()		Return date
const xbString & GetFormattedDate() const
xbString & GetFormattedDate()		 Returns formatted date. See notes on format paramaters.
int IsLeapYear( const char *Date8 ) const
int IsLeapYear( const xbString &Date8 ) const
int IsLeapYear() const		Returns true if given date is a leap year
long JulianDays( const char *Date8 ) const
long JulianDays( const xbString & Date8 ) const
long JulianDays() const		Returns number of days since 1/1/0100 to given date
xbString & JulToDate8( long )Converts julian based date to CCYYMMDD format.
xbString & LastdayOfMonth( const char *Date8 )
xbString & LastDayOfMonth( const xbString & Date8 )
xbString & LastDayOfMonth()		Returns the Date8 format of the last day of the month for a given date
int MonthOf( const char *Date8 ) const
int MonthOf( const xbString &Date8) const
int MonthOf() const		Returns month of a date
int SetDate( const char * Date8 )
int SetDate( const xbString & Date8 )		 Sets the xbDate to Date8. Return 1 on success, 0 on error.
xbString & Sysdate()This method sets the class date and returns the system date
int YearOf( const char *Date8 ) const
int YearOf( const xbString &Date8 ) const
int YearOf() const		Returns century and year of a date
xbString &operator+=( int )+= operator
xbString &operator-=( int )-= operator
xbString &operator++( int )++ operator
xbString &operator--( int )-- operator
xbString &operator+( int )+ operator
xbString &operator-( int )- operator
long operator-( const xbDate & ) const- operator
int operator==( const xbDate & ) const== operator
int operator!=( const xbDate & ) const!= operator
int operator<( const xbDate & ) const< operator
int operator>( const xbDate & ) const> operator
int operator<=( const xbDate & ) const<= operator
int operator>=( const xbDate & ) const>= operator



Sample program


The source for this program is in the libtest directory.

Xbase project source code This program tests the xdate routines Copyright (C) 1997 Gary A. Kunkel This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Contact: Mail: Technology Associates, Inc. XBase Project 1455 Deming Way #11 Sparks, NV 89434 USA Email: xbase@techass.com xdb-devel@lists.sourceforge.net xdb-users@lists.sourceforge.net Website: xdb.sourceforge.net This program tests and demonstrates usage of the various xbDate methods Several of the tests pass either StringDate or Chardate to the method being tested - this is done to test the class methods. In actual usage, this may not be necessary due to the instance of the class already containing a date value. */ #include "xbase.h" int main() { xbString StringDate( "19601007" ); /* oct 7 1960 */ char CharDate[9] = "19611109"; /* nov 9 1961 */ xbDate d1; /* today is default */ xbDate d2( StringDate ); /* from string data */ xbDate d3( CharDate ); /* from char data */ xbDate d4; /* another date class */ std::cout << "This program tests the XDATE routines" << std::endl; std::cout << "Date 1 (Sysdate) is " << d1.GetDate() << std::endl; std::cout << "Date 2 (StringDate) is " << d2.GetDate() << std::endl; std::cout << "Date 3 (CharDate) is " << d3.GetDate() << std::endl; std::cout << "This year is " << d1.YearOf() << std::endl; std::cout << "Year of xbString Date is " << d2.YearOf( StringDate ) << std::endl; std::cout << "Year of char Date is " << d3.YearOf( CharDate ) << std::endl; std::cout << "This Month is " << d1.MonthOf() << std::endl; std::cout << "Month of xbString Date is " << d2.MonthOf( StringDate ) << std::endl; std::cout << "Month of char Date is " << d3.MonthOf( CharDate ) << std::endl; std::cout << "Today is day " << d1.DayOf( XB_FMT_WEEK ) << " of the week" << std::endl; std::cout << "StringDate is day " << d2.DayOf( XB_FMT_MONTH, StringDate ) << " of the month" << std::endl; std::cout << "CharDate is day " << d3.DayOf( XB_FMT_YEAR, CharDate ) << " of the year" << std::endl; if( d1.IsLeapYear()) std::cout << "This is a leapyear" << std::endl; else std::cout << "This is not a leap year." << std::endl; if( d2.IsLeapYear( StringDate )) std::cout << "StringDate is a leapyear" << std::endl; else std::cout << "StringDate is not a leap year." << std::endl; if( d3.IsLeapYear( CharDate )) std::cout << "CharDate is a leapyear" << std::endl; else std::cout << "CharDate is not a leap year." << std::endl; std::cout << "Today is " << d1.Sysdate() << std::endl; if( d1.DateIsValid( "19951301" )) std::cout << "19951301 is a valid date" << std::endl; else std::cout << "19951301 is not a valid date" << std::endl; if( d1.DateIsValid( "19920229" )) std::cout << "19920229 is a valid date" << std::endl; else std::cout << "19920229 is not a valid date" << std::endl; if( d2.DateIsValid( StringDate )) std::cout << StringDate << " is a valid date" << std::endl; else std::cout << StringDate << " is not a valid date" << std::endl; std::cout << "Today's Julian date " << d1.JulianDays() << std::endl; std::cout << "StringDate Julian date " << d2.JulianDays( StringDate ) << std::endl; std::cout << "There are " << ( d1.JulianDays( "19951101" ) - d1.JulianDays( "19951001" )) << " days between 10/1/95 and 11/1/95." << std::endl; std::cout << "Todays Julian date (Number of days since Jan 1 0100):" << d1.JulianDays() << std::endl; d4 = d1; // set d4 class = to sysdate std::cout << "Object d4 initialized to " << d4.GetDate() << std::endl; std::cout << "This should be todays date: " << d4.JulToDate8(d4.JulianDays()) << std::endl; std::cout << "In 7 days it will be " << d4.JulToDate8(d4.JulianDays() + 7L ) << std::endl; std::cout << "Today is " << d1.CharDayOf() << std::endl; std::cout << "StringDate day is " << d2.CharDayOf( StringDate ) << std::endl; std::cout << "This month is " << d1.CharMonthOf() << std::endl; std::cout << "StringDate month is " << d2.CharMonthOf() << std::endl; /* various format routines using different formats, strings and chars */ xbString xbStFmt( "MM/DD/YY" ); std::cout << "Format (YYDDD) " << d1.FormatDate( "YYDDD" ) << std::endl; std::cout << "Format (MM/DD/YY) " << d1.FormatDate( xbStFmt ) << std::endl; xbStFmt = "DD/MM/YY"; std::cout << "Format (DD/MM/YY) " << d1.FormatDate(xbStFmt, "19730110") << std::endl; std::cout << "Format (MMMM DD,YYYY) " << d1.FormatDate( "MMMM DD,YYYY", d1.GetDate()) << std::endl; xbStFmt = "DDDD, MMMM DD YYYY"; std::cout << "Format (DDDD, MMMM DD YYYY) " << d2.FormatDate( xbStFmt, d2.GetDate()) << std::endl; std::cout << "Last day this month " << d1.LastDayOfMonth() << std::endl; std::cout << "Last day of month for StringDate is " << d2.LastDayOfMonth( d2.GetDate()) << std::endl; std::cout << "Overloaded operators test..." << std::endl; if( d1 == d2 ) std::cout << d1.GetDate() << " is equal to " << d2.GetDate() << std::endl; else std::cout << d1.GetDate() << " is not equal to " << d2.GetDate() << std::endl; if( d1 != d3 ) std::cout << d1.GetDate() << " is not equal to " << d3.GetDate() << std::endl; else std::cout << d1.GetDate() << " is equal to " << d3.GetDate() << std::endl; if( d1 < d2 ) std::cout << d1.GetDate() << " is less than " << d2.GetDate() << std::endl; else std::cout << d1.GetDate() << " is not less than " << d2.GetDate() << std::endl; if( d1 > d2 ) std::cout << d1.GetDate() << " is greater than " << d2.GetDate() << std::endl; else std::cout << d1.GetDate() << " is not greater than " << d2.GetDate() << std::endl; if( d1 <= d2 ) std::cout << d1.GetDate() << " is less than or equal to " << d2.GetDate() << std::endl; else std::cout << d1.GetDate() << " is not less than or equal to " << d2.GetDate() << std::endl; if( d1 >= d2 ) std::cout << d1.GetDate() << " is greater than or equal to " << d2.GetDate() << std::endl; else std::cout << d1.GetDate() << " is not greater than or equal to " << d2.GetDate() << std::endl; d1.Sysdate(); d1++; std::cout << "Tomorrow is " << d1.GetDate() << std::endl; d1-=2; std::cout << "Yesterday was " << d1.GetDate() << std::endl; std::cout << "There are " << d1 - d2 << " days between " << d1.GetDate() << " and " << d2.GetDate() << std::endl; return 0; }