QDate(3qt)QDate(3qt)NAMEQDate - Date functions
#include <qdatetime.h>
Public Members
QDate ()
QDate ( int y, int m, int d )
bool isNull () const
bool isValid () const
int year () const
int month () const
int day () const
int dayOfWeek () const
int dayOfYear () const
int daysInMonth () const
int daysInYear () const
virtual QString monthName ( int month ) const
virtual QString dayName ( int weekday ) const
QString toString () const
bool setYMD ( int y, int m, int d )
QDate addDays ( int days ) const
int daysTo ( const QDate & ) const
bool operator== ( const QDate & d ) const
bool operator!= ( const QDate & d ) const
bool operator< ( const QDate & d ) const
bool operator<= ( const QDate & d ) const
bool operator> ( const QDate & d ) const
bool operator>= ( const QDate & d ) const
Static Public Members
QDate currentDate ()
bool isValid ( int y, int m, int d )
bool leapYear ( int year )
Static Protected Members
uint greg2jul ( int y, int m, int d ) (internal)
void jul2greg ( uint jd, int & y, int & m, int & d )
(internal)
RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
QDataStream & operator<< (QDataStream & s, const QDate &
d)
QDataStream & operator>> (QDataStream & s, QDate & d)
DESCRIPTION
The QDate class provides date functions.
A QDate object contains a calendar date, i.e. year, month,
and day numbers in the modern western (Gregorian)
calendar. It can read the current date from the system
clock. It provides functions for comparing dates and for
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manipulating a date by adding a number of days.
A QDate object is typically created either by giving the
year, month and day numbers explicitly, or by using the
static function currentDate(), which makes a QDate object
which contains the system's clock date. An explicit date
can also be set using setYMD().
The year(), month(), and day() functions provide access to
the year, month, and day numbers. Also, dayOfWeek() and
dayOfYear() functions are provided. The same information
is provided in textual format by the toString(),
dayName(), and monthName() functions.
QDate provides a full set of operators to compare two
QDate objects. A date is considered smaller than another
if it is earlier than the other.
The date a given number of days later than a given date
can be found using the addDays() function.
Correspondingly, the number of days between two dates can
be found using the daysTo() function.
The daysInMonth() and daysInYear() functions tell how many
days there are in this date's month and year,
respectively. The isLeapYear() function tells whether this
date is in a leap year.
Note that QDate may not be used for date calculations for
dates in the remote past, i.e. prior to the introduction
of the Gregorian calendar. This calendar was adopted by
England Sep. 14. 1752 (hence this is the earliest valid
QDate), and subsequently by most other western countries,
until 1923.
The end of time is reached around 8000AD, by which time we
expect Qt to be obsolete.
See also QTime and QDateTime.
MEMBER FUNCTION DOCUMENTATIONQDate::QDate ()
Constructs a null date. Null dates are invalid.
See also isNull() and isValid().
QDate::QDate ( int y, int m, int d )
Constructs a date with the year y, month m and day d.
y must be in the range 1752-ca. 8000, m must be in the
range 1-12, and d must be in the range 1-31. Exception: if
y is in the range 0-99, it is interpreted as 1900-1999.
See also isValid().
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QDate(3qt)QDate(3qt)QDate QDate::addDays ( int ndays ) const
Returns a QDate object containing a date ndays later than
the date of this object (or earlier if ndays is negative).
See also daysTo().
QDate QDate::currentDate () [static]
Returns the current date, as reported by the system clock.
See also QTime::currentTime() and
QDateTime::currentDateTime().
int QDate::day () const
Returns the day of the month (1..31) of this date.
See also year(), month() and dayOfWeek().
QString QDate::dayName ( int weekday ) const [virtual]
Returns the name of the weekday.
Weekday 1 == "Mon", day 2 == "Tue" etc.
See also toString() and monthName().
int QDate::dayOfWeek () const
Returns the weekday (Monday=1 .. Sunday=7) for this date.
See also day() and dayOfYear().
int QDate::dayOfYear () const
Returns the day of the year (1..365) for this date.
See also day() and dayOfWeek().
int QDate::daysInMonth () const
Returns the number of days in the month (28..31) for this
date.
See also day() and daysInYear().
int QDate::daysInYear () const
Returns the number of days in the year (365 or 366) for
this date.
See also day() and daysInMonth().
int QDate::daysTo ( const QDate & d ) const
Returns the number of days from this date to d (which is
negative if d is earlier than this date).
Example:
QDate d1( 1995, 5, 17 ); // May 17th 1995
QDate d2( 1995, 5, 20 ); // May 20th 1995
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d1.daysTo( d2 ); // returns 3
d2.daysTo( d1 ); // returns -3
See also addDays().
bool QDate::isNull () const
Returns TRUE if the date is null. A null date is invalid.
See also isValid().
bool QDate::isValid () const
Returns TRUE if this date is valid.
See also isNull().
bool QDate::isValid ( int y, int m, int d ) [static]
Returns TRUE if the specified date (year y, month m and
day d) is valid.
Example:
QDate::isValid( 2002, 5, 17 ); // TRUE; May 17th 2002 is OK.
QDate::isValid( 2002, 2, 30 ); // FALSE; Feb 30th does not exist
QDate::isValid( 2004, 2, 29 ); // TRUE; 2004 is a leap year
QDate::isValid( 1202, 6, 6 ); // FALSE; 1202 is pre-Gregorian
Note that a y value in the range 00-99 is interpreted as
1900-1999.
See also isNull() and setYMD().
bool QDate::leapYear ( int y ) [static]
Returns TRUE if the specified year y is a leap year.
int QDate::month () const
Returns the month (January=1 .. December=12) of this date.
See also year() and day().
QString QDate::monthName ( int month ) const [virtual]
Returns the name of the month.
Month 1 == "Jan", month 2 == "Feb" etc.
See also toString() and dayName().
bool QDate::operator!= ( const QDate & d ) const
Returns TRUE if this date is different from d, or FALSE if
they are equal.
bool QDate::operator<; ( const QDate & d ) const
Returns TRUE if this date is earlier than d, otherwise
FALSE.
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QDate(3qt)QDate(3qt)bool QDate::operator<;= ( const QDate & d ) const
Returns TRUE if this date is earlier than or equal to d,
otherwise FALSE.
bool QDate::operator== ( const QDate & d ) const
Returns TRUE if this date is equal to d, or FALSE if they
are different.
bool QDate::operator> ( const QDate & d ) const
Returns TRUE if this date is later than d, otherwise
FALSE.
bool QDate::operator>= ( const QDate & d ) const
Returns TRUE if this date is later than or equal to d,
otherwise FALSE.
bool QDate::setYMD ( int y, int m, int d )
Sets the year y, month m and day d.
y must be in the range 1752-ca. 8000, m must be in the
range 1-12, and d must be in the range 1-31. Exception: if
y is in the range 0-99, it is interpreted as 1900-1999.
Returns TRUE if the date is valid, otherwise FALSE.
QString QDate::toString () const
Returns the date as a string.
The string format is "Sat May 20 1995". This function uses
the dayName() and monthName() functions to generate the
string.
See also dayName() and monthName().
int QDate::year () const
Returns the year (>= 1752) of this date.
See also month() and day().
uint QDate::greg2jul ( int y, int m, int d ) [static protected]
For internal use only.
void QDate::jul2greg ( uint jd, int & y, int & m, int & d )
[static protected]
For internal use only.
RELATED FUNCTION DOCUMENTATIONQDataStream & operator<;< (QDataStream & s, const QDate & d)
Writes the date to the stream.
See also Format of the QDataStream operators
QDataStream & operator>> (QDataStream & s, QDate & d)
Reads a date from the stream.
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See also Format of the QDataStream operators
SEE ALSO
http://doc.trolltech.com/qdate.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
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http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qdate.3qt) and
the Qt version (2.3.1).
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