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The QDate class provides date functions. More...
#include <qdatetime.h>
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 manipulating dates, e.g. by adding a number of days or months or years.
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 clock's date. An explicit date can also be set using setYMD(). The fromString() function returns a QDate given a string and a date format which is used to interpret the date within the string.
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(), shortDayName(), longDayName(), shortMonthName() and longMonthName() functions.
QDate provides a full set of operators to compare two QDate objects where smaller means earlier and larger means later.
You can increment (or decrement) a date by a given number of days using addDays(). Similarly you can use addMonths() and addYears(). The daysTo() function returns the number of days between two dates.
The daysInMonth() and daysInYear() functions return how many days there are in this date's month and year, respectively. The leapYear() function indicates whether this date is in a leap year.
Note that QDate should not be used for date calculations for dates prior to the introduction of the Gregorian calendar. This calendar was adopted by England from 14th September 1752 (hence this is the earliest valid QDate), and subsequently by most other western countries, until 1923.
The end of time is reached around 8000, by which time we expect Qt to be obsolete.
See also QTime, QDateTime, QDateEdit and QDateTimeEdit.
See also isNull() and isValid().
y must be in the range 1752..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().
See also daysTo().
See also QTime::currentTime() and QDateTime::currentDateTime().
Example: dclock/dclock.cpp.
See also year(), month() and dayOfWeek().
Example: dclock/dclock.cpp.
Use shortDayName() instead.
See also day() and dayOfYear().
See also day() and dayOfWeek().
See also day() and daysInYear().
See also day() and daysInMonth().
Example:
QDate d1( 1995, 5, 17 ); // May 17th 1995 QDate d2( 1995, 5, 20 ); // May 20th 1995 d1.daysTo( d2 ); // returns 3 d2.daysTo( d1 ); // returns -3
See also addDays().
Returns TRUE if the date is null; otherwise returns FALSE. A null date is invalid.
See also isValid().
See also isNull().
Example:
QDate::isValid( 2002, 5, 17 ); // TRUE May 17th 2002 is valid 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().
1 = "Monday", 2 = "Tuesday", ... 7 = "Sunday"
See also toString(), shortDayName(), shortMonthName() and longMonthName().
1 = "January", 2 = "February", ... 12 = "December"
See also toString(), shortMonthName(), shortDayName() and longDayName().
Example: dclock/dclock.cpp.
Use shortMonthName() instead.
The names are used by longDayNames() and toString().
See also setShortMonthNames(), setShortDayNames() and setLongMonthNames().
The names are used by longMonthNames() and toString().
See also setShortMonthNames(), setShortDayNames() and setLongDayNames().
The names are used by shortDayNames() and toString().
See also setShortMonthNames(), setLongMonthNames() and setLongDayNames().
The names are used by shortMonthNames() and toString().
See also setShortDayNames(), setLongMonthNames() and setLongDayNames().
y must be in the range 1752..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 returns FALSE.
1 = "Mon", 2 = "Tue", ... 7 = "Sun"
See also toString(), shortMonthName(), longMonthName() and longDayName().
1 = "Jan", 2 = "Feb", ... 12 = "Dec"
See also toString(), longMonthName(), shortDayName() and longDayName().
If f is Qt::TextDate, the string format is "Sat May 20 1995" (using the shortDayName() and shortMonthName() functions to generate the string).
If f is Qt::ISODate, the string format corresponds to the ISO 8601 specification for representations of dates, which is YYYY-MM-DD where YYYY is the year, MM is the month of the year (between 01 and 12), and DD is the day of the month between 01 and 31.
See also shortDayName() and shortMonthName().
See also Format of the QDataStream operators.
See also Format of the QDataStream operators.
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Copyright © 2001 Trolltech | Trademarks | Qt version 3.0.0-beta1-beta1
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