1QDate(3qt)                                                          QDate(3qt)
2
3
4

NAME

6       QDate - Date functions
7

SYNOPSIS

9       All the functions in this class are reentrant when Qt is built with
10       thread support.</p>
11
12       #include <qdatetime.h>
13
14   Public Members
15       QDate ()
16       QDate ( int y, int m, int d )
17       bool isNull () const
18       bool isValid () const
19       int year () const
20       int month () const
21       int day () const
22       int dayOfWeek () const
23       int dayOfYear () const
24       int daysInMonth () const
25       int daysInYear () const
26       int weekNumber ( int * yearNumber = 0 ) const
27       QString toString ( Qt::DateFormat f = Qt::TextDate ) const
28       QString toString ( const QString & format ) const
29       bool setYMD ( int y, int m, int d )
30       QDate addDays ( int ndays ) const
31       QDate addMonths ( int nmonths ) const
32       QDate addYears ( int nyears ) const
33       int daysTo ( const QDate & d ) const
34       bool operator== ( const QDate & d ) const
35       bool operator!= ( const QDate & d ) const
36       bool operator< ( const QDate & d ) const
37       bool operator<= ( const QDate & d ) const
38       bool operator> ( const QDate & d ) const
39       bool operator>= ( const QDate & d ) const
40
41   Static Public Members
42       QString monthName ( int month )  (obsolete)
43       QString dayName ( int weekday )  (obsolete)
44       QString shortMonthName ( int month )
45       QString shortDayName ( int weekday )
46       QString longMonthName ( int month )
47       QString longDayName ( int weekday )
48       QDate currentDate ()
49       QDate currentDate ( Qt::TimeSpec ts )
50       QDate fromString ( const QString & s, Qt::DateFormat f = Qt::TextDate )
51       bool isValid ( int y, int m, int d )
52       bool leapYear ( int y )
53
55       QDataStream & operator<< ( QDataStream & s, const QDate & d )
56       QDataStream & operator>> ( QDataStream & s, QDate & d )
57

DESCRIPTION

59       The QDate class provides date functions.
60
61       A QDate object contains a calendar date, i.e. year, month, and day
62       numbers, in the modern Western (Gregorian) calendar. It can read the
63       current date from the system clock. It provides functions for comparing
64       dates and for manipulating dates, e.g. by adding a number of days or
65       months or years.
66
67       A QDate object is typically created either by giving the year, month
68       and day numbers explicitly, or by using the static function
69       currentDate(), which creates a QDate object containing the system
70       clock's date. An explicit date can also be set using setYMD(). The
71       fromString() function returns a QDate given a string and a date format
72       which is used to interpret the date within the string.
73
74       The year(), month(), and day() functions provide access to the year,
75       month, and day numbers. Also, dayOfWeek() and dayOfYear() functions are
76       provided. The same information is provided in textual format by the
77       toString(), shortDayName(), longDayName(), shortMonthName() and
78       longMonthName() functions.
79
80       QDate provides a full set of operators to compare two QDate objects
81       where smaller means earlier and larger means later.
82
83       You can increment (or decrement) a date by a given number of days using
84       addDays(). Similarly you can use addMonths() and addYears(). The
85       daysTo() function returns the number of days between two dates.
86
87       The daysInMonth() and daysInYear() functions return how many days there
88       are in this date's month and year, respectively. The leapYear()
89       function indicates whether this date is in a leap year.
90
91       Note that QDate should not be used for date calculations for dates
92       prior to the introduction of the Gregorian calendar. This calendar was
93       adopted by England from the 14<sup><small>th</small></sup> September
94       1752 (hence this is the earliest valid QDate), and subsequently by most
95       other Western countries, until 1923.
96
97       The end of time is reached around the year 8000, by which time we
98       expect Qt to be obsolete.
99
100       See also QTime, QDateTime, QDateEdit, QDateTimeEdit, and Time and Date.
101

MEMBER FUNCTION DOCUMENTATION

QDate::QDate ()

104       Constructs a null date. Null dates are invalid.
105
106       See also isNull() and isValid().
107

QDate::QDate ( int y, int m, int d )

109       Constructs a date with year y, month m and day d.
110
111       y must be in the range 1752..8000, m must be in the range 1..12, and d
112       must be in the range 1..31.
113
114       Warning: If y is in the range 0..99, it is interpreted as 1900..1999.
115
116       See also isValid().
117

QDate QDate::addDays ( int ndays ) const

119       Returns a QDate object containing a date ndays later than the date of
120       this object (or earlier if ndays is negative).
121
122       See also addMonths(), addYears(), and daysTo().
123

QDate QDate::addMonths ( int nmonths ) const

125       Returns a QDate object containing a date nmonths later than the date of
126       this object (or earlier if nmonths is negative).
127
128       See also addDays() and addYears().
129

QDate QDate::addYears ( int nyears ) const

131       Returns a QDate object containing a date nyears later than the date of
132       this object (or earlier if nyears is negative).
133
134       See also addDays() and addMonths().
135

QDate QDate::currentDate ( Qt::TimeSpec ts ) [static]

137       Returns the current date, as reported by the system clock, for the
138       TimeSpec ts. The default TimeSpec is LocalTime.
139
140       See also QTime::currentTime(), QDateTime::currentDateTime(), and
141       Qt::TimeSpec.
142
143       Example: dclock/dclock.cpp.
144

QDate QDate::currentDate () [static]

146       This is an overloaded member function, provided for convenience. It
147       behaves essentially like the above function.
148
149       Returns the current date, as reported by the system clock.
150
151       See also QTime::currentTime() and QDateTime::currentDateTime().
152

int QDate::day () const

154       Returns the day of the month (1..31) of this date.
155
156       See also year(), month(), and dayOfWeek().
157
158       Example: dclock/dclock.cpp.
159

QString QDate::dayName ( int weekday ) [static]

161       This function is obsolete. It is provided to keep old source working.
162       We strongly advise against using it in new code.
163
164       Use shortDayName() instead.
165

int QDate::dayOfWeek () const

167       Returns the weekday (Monday=1..Sunday=7) for this date.
168
169       See also day() and dayOfYear().
170

int QDate::dayOfYear () const

172       Returns the day of the year (1..365) for this date.
173
174       See also day() and dayOfWeek().
175

int QDate::daysInMonth () const

177       Returns the number of days in the month (28..31) for this date.
178
179       See also day() and daysInYear().
180

int QDate::daysInYear () const

182       Returns the number of days in the year (365 or 366) for this date.
183
184       See also day() and daysInMonth().
185

int QDate::daysTo ( const QDate & d ) const

187       Returns the number of days from this date to d (which is negative if d
188       is earlier than this date).
189
190       Example:
191
192               QDate d1( 1995, 5, 17 );  // May 17th 1995
193               QDate d2( 1995, 5, 20 );  // May 20th 1995
194               d1.daysTo( d2 );          // returns 3
195               d2.daysTo( d1 );          // returns -3
196
197       See also addDays().
198

QDate QDate::fromString ( const QString & s, Qt::DateFormat f = Qt::TextDate )

200       [static]
201       Returns the QDate represented by the string s, using the format f, or
202       an invalid date if the string cannot be parsed.
203
204       Note for Qt::TextDate: It is recommended that you use the English short
205       month names (e.g. "Jan"). Although localized month names can also be
206       used, they depend on the user's locale settings.
207
208       Warning: Qt::LocalDate cannot be used here.
209

bool QDate::isNull () const

211       Returns TRUE if the date is null; otherwise returns FALSE. A null date
212       is invalid.
213
214       See also isValid().
215

bool QDate::isValid () const

217       Returns TRUE if this date is valid; otherwise returns FALSE.
218
219       See also isNull().
220

bool QDate::isValid ( int y, int m, int d ) [static]

222       This is an overloaded member function, provided for convenience. It
223       behaves essentially like the above function.
224
225       Returns TRUE if the specified date (year y, month m and day d) is
226       valid; otherwise returns FALSE.
227
228       Example:
229
230           QDate::isValid( 2002, 5, 17 );  // TRUE   May 17th 2002 is valid
231           QDate::isValid( 2002, 2, 30 );  // FALSE  Feb 30th does not exist
232           QDate::isValid( 2004, 2, 29 );  // TRUE   2004 is a leap year
233           QDate::isValid( 1202, 6, 6 );   // FALSE  1202 is pre-Gregorian
234
235       Warning: A y value in the range 00..99 is interpreted as 1900..1999.
236
237       See also isNull() and setYMD().
238

bool QDate::leapYear ( int y ) [static]

240       Returns TRUE if the specified year y is a leap year; otherwise returns
241       FALSE.
242

QString QDate::longDayName ( int weekday ) [static]

244       Returns the long name of the weekday.
245
246       1 = "Monday", 2 = "Tuesday", ... 7 = "Sunday"
247
248       The day names will be localized according to the system's locale
249       settings.
250
251       See also toString(), shortDayName(), shortMonthName(), and
252       longMonthName().
253

QString QDate::longMonthName ( int month ) [static]

255       Returns the long name of the month.
256
257       1 = "January", 2 = "February", ... 12 = "December"
258
259       The month names will be localized according to the system's locale
260       settings.
261
262       See also toString(), shortMonthName(), shortDayName(), and
263       longDayName().
264

int QDate::month () const

266       Returns the month (January=1..December=12) of this date.
267
268       See also year() and day().
269
270       Example: dclock/dclock.cpp.
271

QString QDate::monthName ( int month ) [static]

273       This function is obsolete. It is provided to keep old source working.
274       We strongly advise against using it in new code.
275
276       Use shortMonthName() instead.
277

bool QDate::operator!= ( const QDate & d ) const

279       Returns TRUE if this date is different from d; otherwise returns FALSE.
280

bool QDate::operator< ( const QDate & d ) const

282       Returns TRUE if this date is earlier than d, otherwise returns FALSE.
283

bool QDate::operator<= ( const QDate & d ) const

285       Returns TRUE if this date is earlier than or equal to d, otherwise
286       returns FALSE.
287

bool QDate::operator== ( const QDate & d ) const

289       Returns TRUE if this date is equal to d; otherwise returns FALSE.
290

bool QDate::operator> ( const QDate & d ) const

292       Returns TRUE if this date is later than d, otherwise returns FALSE.
293

bool QDate::operator>= ( const QDate & d ) const

295       Returns TRUE if this date is later than or equal to d, otherwise
296       returns FALSE.
297

bool QDate::setYMD ( int y, int m, int d )

299       Sets the date's year y, month m and day d.
300
301       y must be in the range 1752..8000, m must be in the range 1..12, and d
302       must be in the range 1..31.
303
304       Warning: If y is in the range 0..99, it is interpreted as 1900..1999.
305
306       Returns TRUE if the date is valid; otherwise returns FALSE.
307

QString QDate::shortDayName ( int weekday ) [static]

309       Returns the name of the weekday.
310
311       1 = "Mon", 2 = "Tue", ... 7 = "Sun"
312
313       The day names will be localized according to the system's locale
314       settings.
315
316       See also toString(), shortMonthName(), longMonthName(), and
317       longDayName().
318

QString QDate::shortMonthName ( int month ) [static]

320       Returns the name of the month.
321
322       1 = "Jan", 2 = "Feb", ... 12 = "Dec"
323
324       The month names will be localized according to the system's locale
325       settings.
326
327       See also toString(), longMonthName(), shortDayName(), and
328       longDayName().
329

QString QDate::toString ( const QString & format ) const

331       Returns the date as a string. The format parameter determines the
332       format of the result string.
333
334       These expressions may be used:
335
336       <center>.nf
337
338       </center>
339
340       All other input characters will be ignored.
341
342       Example format strings (assuming that the QDate is the
343       20<sup><small>th</small></sup> July 1969): <center>.nf
344
345       </center>
346
347       If the date is an invalid date, then QString::null will be returned.
348
349       See also QDateTime::toString() and QTime::toString().
350

QString QDate::toString ( Qt::DateFormat f = Qt::TextDate ) const

352       This is an overloaded member function, provided for convenience. It
353       behaves essentially like the above function.
354
355       Returns the date as a string. The f parameter determines the format of
356       the string.
357
358       If f is Qt::TextDate, the string format is "Sat May 20 1995" (using the
359       shortDayName() and shortMonthName() functions to generate the string,
360       so the day and month names are locale specific).
361
362       If f is Qt::ISODate, the string format corresponds to the ISO 8601
363       specification for representations of dates, which is YYYY-MM-DD where
364       YYYY is the year, MM is the month of the year (between 01 and 12), and
365       DD is the day of the month between 01 and 31.
366
367       If f is Qt::LocalDate, the string format depends on the locale settings
368       of the system.
369
370       If the date is an invalid date, then QString::null will be returned.
371
372       See also shortDayName() and shortMonthName().
373

int QDate::weekNumber ( int * yearNumber = 0 ) const

375       Returns the week number (1 to 53), and stores the year in *yearNumber
376       unless yearNumber is null (the default).
377
378       Returns 0 if the date is invalid.
379
380       In accordance with ISO 8601, weeks start on Monday and the first
381       Thursday of a year is always in week 1 of that year. Most years have 52
382       weeks, but some have 53.
383
384       *yearNumber is not always the same as year(). For example, 1 January
385       2000 has week number 52 in the year 1999, and 31 December 2002 has week
386       number 1 in the year 2003.
387
388       Copyright (c) 1989 The Regents of the University of California. All
389       rights reserved.
390
391       Redistribution and use in source and binary forms are permitted
392       provided that the above copyright notice and this paragraph are
393       duplicated in all such forms and that any documentation, advertising
394       materials, and other materials related to such distribution and use
395       acknowledge that the software was developed by the University of
396       California, Berkeley. The name of the University may not be used to
397       endorse or promote products derived from this software without specific
398       prior written permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND
399       WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
400       LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
401       PARTICULAR PURPOSE.
402
403       See also isValid().
404

int QDate::year () const

406       Returns the year (1752..8000) of this date.
407
408       See also month() and day().
409

QDataStream & operator<< ( QDataStream & s, const QDate & d )

412       Writes the date, d, to the data stream, s.
413
414       See also Format of the QDataStream operators.
415

QDataStream & operator>> ( QDataStream & s, QDate & d )

417       Reads a date from the stream s into d.
418
419       See also Format of the QDataStream operators.
420
421

SEE ALSO

423       http://doc.trolltech.com/qdate.html
424       http://www.trolltech.com/faq/tech.html
425
427       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
428       license file included in the distribution for a complete license
429       statement.
430

AUTHOR

432       Generated automatically from the source code.
433

BUGS

435       If you find a bug in Qt, please report it as described in
436       http://doc.trolltech.com/bughowto.html.  Good bug reports help us to
437       help you. Thank you.
438
439       The definitive Qt documentation is provided in HTML format; it is
440       located at $QTDIR/doc/html and can be read using Qt Assistant or with a
441       web browser. This man page is provided as a convenience for those users
442       who prefer man pages, although this format is not officially supported
443       by Trolltech.
444
445       If you find errors in this manual page, please report them to qt-
446       bugs@trolltech.com.  Please include the name of the manual page
447       (qdate.3qt) and the Qt version (3.3.8).
448
449
450
451Trolltech AS                    2 February 2007                     QDate(3qt)
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