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Eneboo - Documentación para desarrolladores
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Eneboo - Documentación para desarrolladores
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The QDateTime class provides date and time functions. Más...
#include <qdatetime.h>
The QDateTime class provides date and time functions.
A QDateTime object contains a calendar date and a clock time (a "datetime"). It is a combination of the QDate and QTime classes. It can read the current datetime from the system clock. It provides functions for comparing datetimes and for manipulating a datetime by adding a number of seconds, days, months or years.
A QDateTime object is typically created either by giving a date and time explicitly in the constructor, or by using the static function currentDateTime(), which returns a QDateTime object set to the system clock's time. The date and time can be changed with setDate() and setTime(). A datetime can also be set using the setTime_t() function, which takes a POSIX-standard "number of seconds since 00:00:00 on January 1, 1970" value. The fromString() function returns a QDateTime given a string and a date format which is used to interpret the date within the string.
The date() and time() functions provide access to the date and time parts of the datetime. The same information is provided in textual format by the toString() function.
QDateTime provides a full set of operators to compare two QDateTime objects where smaller means earlier and larger means later.
You can increment (or decrement) a datetime by a given number of seconds using addSecs() or days using addDays(). Similarly you can use addMonths() and addYears(). The daysTo() function returns the number of days between two datetimes, and secsTo() returns the number of seconds between two datetimes.
The range of a datetime object is constrained to the ranges of the QDate and QTime objects which it embodies.
| QDateTime::QDateTime | ( | ) | [inline] |
Constructs a null datetime (i.e. null date and null time). A null datetime is invalid, since the date is invalid.
| QDateTime::QDateTime | ( | const QDate & | date | ) |
Constructs a datetime with date date and null (but valid) time (00:00:00.000).
Constructs a datetime with date date and time time.
| QDateTime::QDateTime | ( | ) | [inline] |
| QDateTime::QDateTime | ( | const QDate & | ) |
Returns a QDateTime object containing a datetime ndays days later than the datetime of this object (or earlier if ndays is negative).
Returns a QDateTime object containing a datetime nmonths months later than the datetime of this object (or earlier if nmonths is negative).
Returns a QDateTime object containing a datetime nsecs seconds later than the datetime of this object (or earlier if nsecs is negative).
Returns a QDateTime object containing a datetime nyears years later than the datetime of this object (or earlier if nyears is negative).
| static QDateTime QDateTime::currentDateTime | ( | Qt::TimeSpec | ) | [static] |
| QDateTime QDateTime::currentDateTime | ( | ) | [static] |
Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. Returns the current datetime, as reported by the system clock.
| QDateTime QDateTime::currentDateTime | ( | Qt::TimeSpec | ts | ) | [static] |
Returns the current datetime, as reported by the system clock, for the TimeSpec ts. The default TimeSpec is LocalTime.
| static QDateTime QDateTime::currentDateTime | ( | ) | [static] |
| QDate QDateTime::date | ( | ) | const [inline] |
| QDate QDateTime::date | ( | ) | const [inline] |
| QDateTime QDateTime::fromString | ( | const QString & | s, |
| Qt::DateFormat | f = Qt::TextDate |
||
| ) | [static] |
Returns the QDateTime represented by the string s, using the format f, or an invalid datetime if this is not possible.
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.
Qt::LocalDate cannot be used here. | static QDateTime QDateTime::fromString | ( | const QString & | s, |
| Qt::DateFormat | f = Qt::TextDate |
||
| ) | [static] |
| bool QDateTime::isNull | ( | ) | const [inline] |
Returns TRUE if both the date and the time are null; otherwise returns FALSE. A null datetime is invalid.
| bool QDateTime::isNull | ( | ) | const [inline] |
| bool QDateTime::isValid | ( | void | ) | const [inline] |
Returns TRUE if both the date and the time are valid; otherwise returns FALSE.
| bool QDateTime::isValid | ( | void | ) | const [inline] |
Returns TRUE if this datetime is different from dt; otherwise returns FALSE.
Returns TRUE if this datetime is earlier than dt; otherwise returns FALSE.
Returns TRUE if this datetime is earlier than or equal to dt; otherwise returns FALSE.
Returns TRUE if this datetime is equal to dt; otherwise returns FALSE.
Returns TRUE if this datetime is later than dt; otherwise returns FALSE.
Returns TRUE if this datetime is later than or equal to dt; otherwise returns FALSE.
Returns the number of seconds from this datetime to dt (which is negative if dt is earlier than this datetime).
Example:
QDateTime dt = QDateTime::currentDateTime(); QDateTime xmas( QDate(dt.date().year(),12,24), QTime(17,00) ); qDebug( "There are %d seconds to Christmas", dt.secsTo(xmas) );
| void QDateTime::setDate | ( | const QDate & | date | ) | [inline] |
| void QDateTime::setDate | ( | const QDate & | date | ) | [inline] |
| void QDateTime::setTime | ( | const QTime & | time | ) | [inline] |
| void QDateTime::setTime | ( | const QTime & | time | ) | [inline] |
| void QDateTime::setTime_t | ( | uint | secsSince1Jan1970UTC | ) |
Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. Convenience function that sets the date and time to local time based on the given UTC time.
| void QDateTime::setTime_t | ( | uint | secsSince1Jan1970UTC, |
| Qt::TimeSpec | |||
| ) |
| void QDateTime::setTime_t | ( | uint | secsSince1Jan1970UTC | ) |
| void QDateTime::setTime_t | ( | uint | secsSince1Jan1970UTC, |
| Qt::TimeSpec | ts | ||
| ) |
Sets the date and time to ts time (Qt::LocalTime or Qt::UTC) given the number of seconds that have passed since 1970-01-01T00:00:00, Coordinated Universal Time (UTC). On systems that do not support timezones this function will behave as if local time were UTC.
On Windows, only a subset of secsSince1Jan1970UTC values are supported, as Windows starts counting from 1980.
| QTime QDateTime::time | ( | ) | const [inline] |
| QTime QDateTime::time | ( | ) | const [inline] |
Returns the datetime as a string. The format parameter determines the format of the result string.
These expressions may be used for the date:
Expression Output d the day as number without a leading zero (1-31) dd the day as number with a leading zero (01-31) ddd the abbreviated localized day name (e.g. 'Mon'..'Sun'). Uses QDate::shortDayName(). dddd the long localized day name (e.g. 'Monday'..'Sunday'). Uses QDate::longDayName(). M the month as number without a leading zero (1-12) MM the month as number with a leading zero (01-12) MMM the abbreviated localized month name (e.g. 'Jan'..'Dec'). Uses QDate::shortMonthName(). MMMM the long localized month name (e.g. 'January'..'December'). Uses QDate::longMonthName(). yy the year as two digit number (00-99) yyyy the year as four digit number (1752-8000)
These expressions may be used for the time:
Expression Output h the hour without a leading zero (0..23 or 1..12 if AM/PM display) hh the hour with a leading zero (00..23 or 01..12 if AM/PM display) m the minute without a leading zero (0..59) mm the minute with a leading zero (00..59) s the second whithout a leading zero (0..59) ss the second whith a leading zero (00..59) z the milliseconds without leading zeroes (0..999) zzz the milliseconds with leading zeroes (000..999) AP use AM/PM display. AP will be replaced by either "AM" or "PM". ap use am/pm display. ap will be replaced by either "am" or "pm".
All other input characters will be ignored.
Example format strings (assumed that the QDateTime is 21st May 2001 14:13:09)
Format Result dd.MM.yyyy 21.05.2001 ddd MMMM d yy Tue May 21 01 hh:mm:ss.zzz 14:13:09.042 h:m:s ap 2:13:9 pm
If the datetime is an invalid datetime, then QString::null will be returned.
| QString QDateTime::toString | ( | Qt::DateFormat | f = Qt::TextDate | ) | const |
Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. Returns the datetime as a string. The f parameter determines the format of the string.
If f is Qt::TextDate, the string format is "Wed May 20
03:40:13 1998" (using QDate::shortDayName(), QDate::shortMonthName(), and QTime::toString() to generate the string, so the day and month names will have localized names).
If f is Qt::ISODate, the string format corresponds to the ISO 8601 extended specification for representations of dates and times, which is YYYY-MM-DDTHH:MM:SS.
If f is Qt::LocalDate, the string format depends on the locale settings of the system.
If the format f is invalid or the datetime is invalid, toString() returns a null string.
| QString QDateTime::toString | ( | Qt::DateFormat | f = Qt::TextDate | ) | const |
| uint QDateTime::toTime_t | ( | ) | const |
| uint QDateTime::toTime_t | ( | ) | const |
Returns the datetime as the number of seconds that have passed since 1970-01-01T00:00:00, Coordinated Universal Time (UTC).
On systems that do not support timezones, this function will behave as if local time were UTC.
| QDataStream & operator<< | ( | QDataStream & | s, |
| const QDateTime & | dt | ||
| ) | [friend] |
Writes the datetime dt to the stream s.
| Q_EXPORT QDataStream& operator<< | ( | QDataStream & | , |
| const QDateTime & | |||
| ) | [friend] |
| Q_EXPORT QDataStream& operator>> | ( | QDataStream & | , |
| QDateTime & | |||
| ) | [friend] |
| QDataStream & operator>> | ( | QDataStream & | s, |
| QDateTime & | dt | ||
| ) | [friend] |
Reads a datetime from the stream s into dt.
1.7.4