QDate Class Reference

Constructs a null date. Null dates are invalid.

See also isNull() and isValid().

Constructs a date with year y, month m and day d.

If the specified date is invalid, the date is not set and isValid() returns false. A date before 2 January 4713 B.C. is considered invalid.

Warning: Years 0 to 99 are interpreted as is, i.e., years 0-99.

See also isValid().

Returns a QDate object containing a date ndays later than the date of this object (or earlier if ndays is negative).

See also addMonths(), addYears(), and daysTo().

Returns a QDate object containing a date nmonths later than the date of this object (or earlier if nmonths is negative).

Note: If the ending day/month combination does not exist in the resulting month/year, this function will return a date that is the latest valid date.

Warning: QDate has a date hole around the days introducing the Gregorian calendar (the days 5 to 14 October 1582, inclusive, do not exist). If the calculation ends in one of those days, QDate will return either October 4 or October 15.

See also addDays() and addYears().

Returns a QDate object containing a date nyears later than the date of this object (or earlier if nyears is negative).

Note: If the ending day/month combination does not exist in the resulting year (i.e., if the date was Feb 29 and the final year is not a leap year), this function will return a date that is the latest valid date (that is, Feb 28).

See also addDays() and addMonths().

Returns the current date, as reported by the system clock.

See also QTime::currentTime() and QDateTime::currentDateTime().

Returns the day of the month (1 to 31) of this date.

See also year(), month(), and dayOfWeek().

Returns the weekday (1 to 7) for this date.

See also day(), dayOfYear(), and Qt::DayOfWeek.

Returns the day of the year (1 to 365 or 366 on leap years) for this date.

See also day() and dayOfWeek().

Returns the number of days in the month (28 to 31) for this date.

See also day() and daysInYear().

Returns the number of days in the year (365 or 366) for this date.

See also day() and daysInMonth().

Returns the number of days from this date to d (which is negative if d is earlier than this date).

Example:

See also addDays().

Converts the Julian day jd to a QDate.

See also toJulianDay().

Returns the QDate represented by the string, using the format given, or an invalid date if the string cannot be parsed.

Note for Qt::TextDate: It is recommended that you use the English short month names (e.g. "Jan"). Although localized month names can also be used, they depend on the user's locale settings.

Returns the QDate represented by the string, using the format given, or an invalid date if the string cannot be parsed.

These expressions may be used for the format:

All other input characters will be treated as text. Any sequence of characters that are enclosed in single quotes will also be treated as text and will not be used as an expression. For example:

If the format is not satisfied, an invalid QDate is returned. The expressions that don't expect leading zeroes (d, M) will be greedy. This means that they will use two digits even if this will put them outside the accepted range of values and leaves too few digits for other sections. For example, the following format string could have meant January 30 but the M will grab two digits, resulting in an invalid date:

For any field that is not represented in the format the following defaults are used:

The following examples demonstrate the default values:

See also QDateTime::fromString(), QTime::fromString(), QDate::toString(), QDateTime::toString(), and QTime::toString().

Extracts the date's year, month, and day, and assigns them to *year, *month, and *day. The pointers may be null.

See also year(), month(), day(), and isValid().

Returns true if the specified year is a leap year; otherwise returns false.

Returns true if the date is null; otherwise returns false. A null date is invalid.

Note: The behavior of this function is equivalent to isValid().

See also isValid().

Returns true if this date is valid; otherwise returns false.

See also isNull().

This is an overloaded function.

Returns true if the specified date (year, month, and day) is valid; otherwise returns false.

Example:

See also isNull() and setDate().

Returns the long version of the name of the weekday. The returned name is in normal type which can be used for date formatting.

See also toString(), shortDayName(), shortMonthName(), and longMonthName().

Returns the long name of the weekday for the representation specified by type.

The days are enumerated using the following convention:

• 1 = "Monday"
• 2 = "Tuesday"
• 3 = "Wednesday"
• 4 = "Thursday"
• 5 = "Friday"
• 6 = "Saturday"
• 7 = "Sunday"

The day names will be localized according to the system's locale settings.

See also toString(), shortDayName(), shortMonthName(), and longMonthName().

Returns the long version of the name of the month. The returned name is in normal type which can be used for date formatting.

See also toString(), shortMonthName(), shortDayName(), and longDayName().

Returns the long name of the month for the representation specified by type.

The months are enumerated using the following convention:

• 1 = "January"
• 2 = "February"
• 3 = "March"
• 4 = "April"
• 5 = "May"
• 6 = "June"
• 7 = "July"
• 8 = "August"
• 9 = "September"
• 10 = "October"
• 11 = "November"
• 12 = "December"

The month names will be localized according to the system's locale settings.

See also toString(), shortMonthName(), shortDayName(), and longDayName().

Returns the number corresponding to the month of this date, using the following convention:

• 1 = "January"
• 2 = "February"
• 3 = "March"
• 4 = "April"
• 5 = "May"
• 6 = "June"
• 7 = "July"
• 8 = "August"
• 9 = "September"
• 10 = "October"
• 11 = "November"
• 12 = "December"

See also year() and day().

Sets the date's year, month, and day. Returns true if the date is valid; otherwise returns false.

If the specified date is invalid, the QDate object is set to be invalid. Any date before 2 January 4713 B.C. is considered invalid.

See also isValid().

Returns the short version of the name of the weekday. The returned name is in normal type which can be used for date formatting.

See also toString(), longDayName(), shortMonthName(), and longMonthName().

Returns the short name of the weekday for the representation specified by type.

The days are enumerated using the following convention:

• 1 = "Mon"
• 2 = "Tue"
• 3 = "Wed"
• 4 = "Thu"
• 5 = "Fri"
• 6 = "Sat"
• 7 = "Sun"

The day names will be localized according to the system's locale settings.

See also toString(), shortMonthName(), longMonthName(), and longDayName().

Returns the short version of the name of the month. The returned name is in normal type which can be used for date formatting.

See also toString(), longMonthName(), shortDayName(), and longDayName().

Returns the short name of the month for the representation specified by type.

The months are enumerated using the following convention:

• 1 = "Jan"
• 2 = "Feb"
• 3 = "Mar"
• 4 = "Apr"
• 5 = "May"
• 6 = "Jun"
• 7 = "Jul"
• 8 = "Aug"
• 9 = "Sep"
• 10 = "Oct"
• 11 = "Nov"
• 12 = "Dec"

The month names will be localized according to the system's locale settings.

See also toString(), longMonthName(), shortDayName(), and longDayName().

Converts the date to a Julian day.

See also fromJulianDay().

Returns the date as a string. The format parameter determines the format of the result string.

These expressions may be used:

All other input characters will be ignored. Any sequence of characters that are enclosed in singlequotes will be treated as text and not be used as an expression. Two consecutive singlequotes ("''") are replaced by a singlequote in the output.

Example format strings (assuming that the QDate is the 20 July 1969):

If the datetime is invalid, an empty string will be returned.

Warning: The Qt::ISODate format is only valid for years in the range 0 to 9999. This restriction may apply to locale-aware formats as well, depending on the locale settings.

See also QDateTime::toString() and QTime::toString().

This is an overloaded function.

Returns the date as a string. The format parameter determines the format of the string.

If the format is Qt::TextDate, the string is formatted in the default way. QDate::shortDayName() and QDate::shortMonthName() are used to generate the string, so the day and month names will be localized names. An example of this formatting is "Sat May 20 1995".

If the format is Qt::ISODate, the string format corresponds to the ISO 8601 extended specification for representations of dates and times, taking the form 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 the format is Qt::SystemLocaleShortDate or Qt::SystemLocaleLongDate, the string format depends on the locale settings of the system. Identical to calling QLocale::system().toString(date, QLocale::ShortFormat) or QLocale::system().toString(date, QLocale::LongFormat).

If the format is Qt::DefaultLocaleShortDate or Qt::DefaultLocaleLongDate, the string format depends on the default application locale. This is the locale set with QLocale::setDefault(), or the system locale if no default locale has been set. Identical to calling QLocale().toString(date, QLocale::ShortFormat) or QLocale().toString(date, QLocale::LongFormat).

If the date is invalid, an empty string will be returned.

Warning: The Qt::ISODate format is only valid for years in the range 0 to 9999. This restriction may apply to locale-aware formats as well, depending on the locale settings.

See also shortDayName() and shortMonthName().

Returns the week number (1 to 53), and stores the year in *yearNumber unless yearNumber is null (the default).

Returns 0 if the date is invalid.

In accordance with ISO 8601, weeks start on Monday and the first Thursday of a year is always in week 1 of that year. Most years have 52 weeks, but some have 53.

*yearNumber is not always the same as year(). For example, 1 January 2000 has week number 52 in the year 1999, and 31 December 2002 has week number 1 in the year 2003.

Copyright (c) 1989 The Regents of the University of California. All rights reserved.

Redistribution and use in source and binary forms are permitted provided that the above copyright notice and this paragraph are duplicated in all such forms and that any documentation, advertising materials, and other materials related to such distribution and use acknowledge that the software was developed by the University of California, Berkeley. The name of the University may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

See also isValid().

Returns the year of this date. Negative numbers indicate years before 1 A.D. = 1 C.E., such that year -44 is 44 B.C.

See also month() and day().

Returns true if this date is different from d; otherwise returns false.

Returns true if this date is earlier than d; otherwise returns false.

Returns true if this date is earlier than or equal to d; otherwise returns false.

Returns true if this date is equal to d; otherwise returns false.

Returns true if this date is later than d; otherwise returns false.

Returns true if this date is later than or equal to d; otherwise returns false.

Sets the date's year y, month m, and day d.

If y is in the range 0 to 99, it is interpreted as 1900 to 1999.

Use setDate() instead.

If spec is Qt::LocalTime, use the currentDate() overload that takes no parameters instead; otherwise, use QDateTime::currentDateTime().

For example, if you have code like

you can rewrite it as

See also QDateTime::toUTC().

Use shortDayName() instead.

Use isLeapYear() instead.

Use shortMonthName() instead.