Home | All Classes | Main Classes | Annotated | Grouped Classes | Functions |
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, QDateTimeEdit and Time and Date.
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().
Qt::LocalDate cannot be used here.
Note for Qt::TextDate: It is recommended to use the English short month names (e.g. Jan). Localized month names may also be used, but they depend on the user's locale settings.
Returns TRUE if the date is null; otherwise returns FALSE. A null date is invalid.
See also isValid().
See also isNull().
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 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"
The day names will be localized according to the system's locale settings.
See also toString(), shortDayName(), shortMonthName() and longMonthName().
1 = "January", 2 = "February", ... 12 = "December"
The month names will be localized according to the system's locale settings.
See also toString(), shortMonthName(), shortDayName() and longDayName().
Example: dclock/dclock.cpp.
Use shortMonthName() instead.
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"
The day names will be localized according to the system's locale settings.
See also toString(), shortMonthName(), longMonthName() and longDayName().
1 = "Jan", 2 = "Feb", ... 12 = "Dec"
The month names will be localized according to the system's locale settings.
See also toString(), longMonthName(), shortDayName() and longDayName().
These expressions may be used:
All other input characters will be ignored.
Example format Strings (assumed that the QDate is 21. May 2001)
See also QDate::toString() and QTime::toString().
Returns the date as a string. The f parameter determines the format of the string.
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.
If f is Qt::LocalDate, the string format depends on the locale settings of the system.
See also shortDayName() and shortMonthName().
See also Format of the QDataStream operators.
See also Format of the QDataStream operators.
This file is part of the Qt toolkit. Copyright © 1995-2002 Trolltech. All Rights Reserved.
Copyright © 2002 Trolltech | Trademarks | Qt version 3.0.4
|