Dates

Chapter Updated 04/28/23



Class xbDate methods

MethodDescription
xbDate()
xbDate( const char * Date8 )
xbDate( const xbString &Date8 )
xbDate( xbInt32 lJulDate )		xbDate constructor.
xbDate( xbUInt16 iInit )Special xbDate constructor, called to initialize static variables and/or set to Sysdate
void operator=( const xbDate &d )Set a date equal to another date.
void operator+=( xbInt32 i )Increment a date.
void operator-=( xbInt32 i )Decrement a date.
void operator++( xbInt32 i )Increment a date.
void operator--( xbInt32 i )Decrement a date.
xbInt32 operator-( const xbDate & ) constDetermine the number of days between two dates.
const char * operator-( xbInt32 i )Subtract i days from a date.
const char * operator+( xbInt32 i )Add i days to a date.
xbBool operator==( const xbDate & ) constCompare for equal dates.
xbBool operator!=( const xbDate & ) constCompare for not equal dates.
xbBool operator< ( const xbDate & ) constCompare for less than date.
xbBool operator> ( const xbDate & ) constCompare for greater than date.
xbBool operator<=( const xbDate & ) constCompare for less than or euql to date.
xbBool operator>=( const xbDate & ) constCompare for greater than or equal to date.
xbInt16 CalcRollingCenturyForYear( xbInt16 year ) constCalculate century for a give 2 digit year. Uses 80/20 method.
xbInt16 CenturyOf() constReturn century of the date.
xbInt16 CharDayOf( xbString &sOutCharDay )Retrieve the character day.
xbInt16 CharMonthOf( xbString &sOutCharMonth )Retrive the character month.
xbBool DateIsValid ( const xbString &sDate8 ) const;Check if a given date is valid.
xbInt16 DayOf( xbInt16 iFormat ) constReturn Day of week, month or year depending on the option.
xbInt16 CTOD( const xbString &sCtodInDate )Sets the date from input date in format MM/DD/YY
xbInt16 FormatDate( const xbString &sFmtIn, xbString &sFmtOut )Create a formatted date string based on input format.
const char *Str() constReturn a pointer the date value.
xbBool IsLeapYear( xbInt16 iYear ) const
IsLeapYear() const		Returns true if leap year, otherwise returns false.
xbBool IsNull() constReturns xbTrue is the date is null, else returns false.
xbInt32 JulianDays() constReturn the Julian days value.
xbInt16 JulToDate8( xbInt32 lJulDate )Convert a Julian date to xbDate value.
xbInt16 LastDayOfMonth()Calculate the last day of a month for the given teat and month.
xbInt16 MonthOf() constReturn the numeric month of the date.
xbInt16 Set( const xbString &Date8 )Set the date to valid input date.
xbInt16 Sysdate()Set the date to the system date.
xbInt16 YearOf() constReturn the numeric year of the date.




Example program using xbDate class

/* xb_ex_date.cpp XBase64 Software Library Copyright (c) 1997,2003,2014,2021,2022 Gary A Kunkel The xb64 software library is covered under the terms of the GPL Version 3, 2007 license. Email Contact: XDB-devel@lists.sourceforge.net XDB-users@lists.sourceforge.net This program demonstrates using the xbDate class */ #include "xbase.h" using namespace xb; int main() { xbXBase x; /* initial date static variables */ 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 */ xbString s; std::cout << "This program demonstrates usage of the xbDate class" << std::endl; std::cout << "Date 1 (Sysdate) is " << d1.Str() << std::endl; std::cout << "Date 2 (StringDate) is " << d2.Str() << std::endl; std::cout << "Date 3 (CharDate) is " << d3.Str() << std::endl; std::cout << "This year is " << d1.YearOf() << std::endl; std::cout << "Year of xbString Date is " << d2.YearOf() << std::endl; std::cout << "Year of char Date is " << d3.YearOf() << std::endl; std::cout << "This Month is " << d1.MonthOf() << std::endl; std::cout << "Month of xbString Date is " << d2.MonthOf() << std::endl; std::cout << "Month of char Date is " << d3.MonthOf() << 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 ) << " of the month" << std::endl; std::cout << "CharDate is day " << d3.DayOf( XB_FMT_YEAR ) << " of the year" << std::endl; if( d1.IsLeapYear()) std::cout << "This is a leap year" << std::endl; else std::cout << "This is not a leap year." << std::endl; if( d2.IsLeapYear()) std::cout << "StringDate is a leap year" << std::endl; else std::cout << "StringDate is not a leap year." << std::endl; if( d3.IsLeapYear()) std::cout << "CharDate is a leap year" << 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.Str() << " is a valid date" << std::endl; else std::cout << StringDate.Str() << " is not a valid date" << std::endl; std::cout << "Today's Julian date " << d1.JulianDays() << std::endl; std::cout << "Julian date of Jan 01, 1970 " << d2.JulianDays() << std::endl; std::cout << "StringDate Julian date " << d2.JulianDays() << std::endl; std::cout << "There are " << (d1.JulianDays() - d2.JulianDays()) << " days between " << d1.Str() << " and " << d2.Str() << 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.Str() << 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; d1.CharDayOf( s ); std::cout << "Today is " << s.Str() << std::endl; d2.CharDayOf( s ); std::cout << "StringDate day is " << s.Str() << std::endl; d1.CharMonthOf( s ); std::cout << "This month is " << s.Str() << std::endl; d2.CharMonthOf( s ); std::cout << "StringDate month is " << s.Str() << std::endl; /* various format routines using different formats, strings and chars */ xbString sOutDate; d1.FormatDate( "YYDDD", sOutDate ); std::cout << "Format (YYDDD) = " << sOutDate.Str() << std::endl; d1.FormatDate( "MM/DD/YY", sOutDate ); std::cout << "Format (MM/DD/YY) = " << sOutDate.Str() << std::endl; d1.FormatDate( "YY-MM-DD", sOutDate ); std::cout << "Format (YY-MM-DD) = " << sOutDate.Str() << std::endl; d1.FormatDate( "DDDDDDDDD, MMMMMMMMMM DD YYYY", sOutDate ); std::cout << "Format (DDDDDDDDD, MMMMMMMMMM DD YYYY) = " << sOutDate.Str() << std::endl; std::cout << "Last day this month " << d1.LastDayOfMonth() << std::endl; std::cout << "Last day of month for StringDate is " << d2.LastDayOfMonth() << std::endl; std::cout << "Overloaded operators test..." << std::endl; if( d1 == d2 ) std::cout << d1.Str() << " is equal to " << d2.Str() << std::endl; else std::cout << d1.Str() << " is not equal to " << d2.Str() << std::endl; if( d1 != d3 ) std::cout << d1.Str() << " is not equal to " << d3.Str() << std::endl; else std::cout << d1.Str() << " is equal to " << d3.Str() << std::endl; if( d1 < d2 ) std::cout << d1.Str() << " is less than " << d2.Str() << std::endl; else std::cout << d1.Str() << " is not less than " << d2.Str() << std::endl; if( d1 > d2 ) std::cout << d1.Str() << " is greater than " << d2.Str() << std::endl; else std::cout << d1.Str() << " is not greater than " << d2.Str() << std::endl; if( d1 <= d2 ) std::cout << d1.Str() << " is less than or equal to " << d2.Str() << std::endl; else std::cout << d1.Str() << " is not less than or equal to " << d2.Str() << std::endl; if( d1 >= d2 ) std::cout << d1.Str() << " is greater than or equal to " << d2.Str() << std::endl; else std::cout << d1.Str() << " is not greater than or equal to " << d2.Str() << std::endl; d1.Sysdate(); d1++; std::cout << "Tomorrow is " << d1.Str() << std::endl; d1-=2; std::cout << "Yesterday was " << d1.Str() << std::endl; std::cout << "There are " << d1 - d2 << " days between " << d1.Str() << " and " << d2.Str() << std::endl; d1="20140701"; std::cout << "Operator = example " << d1.Str() << std::endl; d1+=5; std::cout << "Operator += 5 example " << d1.Str() << std::endl; d1--; std::cout << "Operator -- example " << d1.Str() << std::endl; d1-4; std::cout << "Operator -4 example " << d1.Str() << std::endl; d1+10; std::cout << "Operator +10 example " << d1.Str() << std::endl; std::cout << "CenturyOf() " << d1.CenturyOf() << std::endl; xbString sWorkDate; d1.CTOD( "10/07/60" ); std::cout << "CTOD( '10/07/60' ) " << d1.Str() << std::endl; d1.Set( "19590118" ); std::cout << "Set( '19590118' ) " << d1.Str() << std::endl; std::cout << "CalcRollingCenturyForYear( 95 ) = " << d1.CalcRollingCenturyForYear( 95 ) << std::endl; return 0; }