QTime(3qt)QTime(3qt)NAME
QTime - Clock time functions
#include <qdatetime.h>
Public Members
QTime ()
QTime ( int h, int m, int s=0, int ms=0 )
bool isNull () const
bool isValid () const
int hour () const
int minute () const
int second () const
int msec () const
QString toString () const
bool setHMS ( int h, int m, int s, int ms=0 )
QTime addSecs ( int secs ) const
int secsTo ( const QTime & ) const
QTime addMSecs ( int ms ) const
int msecsTo ( const QTime & ) const
bool operator== ( const QTime & d ) const
bool operator!= ( const QTime & d ) const
bool operator< ( const QTime & d ) const
bool operator<= ( const QTime & d ) const
bool operator> ( const QTime & d ) const
bool operator>= ( const QTime & d ) const
void start ()
int restart ()
int elapsed ()
Static Public Members
QTime currentTime ()
bool isValid ( int h, int m, int s, int ms=0 )
RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
QDataStream & operator>> (QDataStream & s, QTime & t)
QDataStream & operator<< (QDataStream & s, const QTime &
t)
DESCRIPTION
The QTime class provides clock time functions.
A QTime object contains a clock time, i.e. a number of
hours, minutes, seconds and milliseconds since midnight.
It can read the current time from the system clock, and
measure a span of elapsed time. It provides functions for
comparing times and for manipulating a time by adding a
number of (milli)seconds.
QTime operates with 24-hour clock format; it has no
concept of AM/PM. It operates with local time; it does not
know anything about time zones or daylight savings time.
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QTime(3qt)QTime(3qt)
A QTime object is typically created either by giving the
number of hours, minutes, seconds, and milliseconds
explicitly, or by using the static function currentTime(),
which makes a QTime object which contains the system's
clock time. Note that the accuracy depends on the accuracy
of the underlying operating system; not all systems
provide 1-millisecond accuracy.
The hour(), minute(), second(), and msec() functions
provide access to the number of hours, minutes, seconds,
and milliseconds of the time. The same information is
provided in textual format by the toString() function.
QTime provides a full set of operators to compare two
QTime objects. A time is considered smaller than another
if it is earlier than the other.
The time a given number of seconds or milliseconds later
than a given time can be found using the addSecs() or
addMSecs() functions. Correspondingly, the number of
(milli)seconds between two times can be found using the
secsTo() or msecsTo() functions.
QTime can be used to measure a span of elapsed time using
the start(), restart(), and elapsed() functions.
See also QDate and QDateTime.
MEMBER FUNCTION DOCUMENTATIONQTime::QTime ()
Constructs the time 0 hours, minutes, seconds and
milliseconds, i.e. 00:00:00.000 (midnight). This is a
valid time.
See also isValid().
QTime::QTime ( int h, int m, int s=0, int ms=0 )
Constructs a time with hour h, minute m, seconds s and
milliseconds ms.
h must be in the range 0-23, m and s must be in the range
0-59, and ms must be in the range 0-999.
See also isValid().
QTime QTime::addMSecs ( int ms ) const
Returns a QTime object containing a time ms milliseconds
later than the time of this object (or earlier if ms is
negative).
Note that the time will wrap if it passes midnight. See
addSecs() for an example.
See also addSecs() and msecsTo().
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QTime(3qt)QTime(3qt)QTime QTime::addSecs ( int nsecs ) const
Returns a QTime object containing a time nsecs seconds
later than the time of this object (or earlier if ms is
negative).
Note that the time will wrap if it passes midnight.
Example:
QTime n( 14, 0, 0 ); // n == 14:00:00
QTime t;
t = n.addSecs( 70 ); // t == 14:01:10
t = n.addSecs( -70 ); // t == 13:58:50
t = n.addSecs( 10*60*60 + 5 ); // t == 00:00:05
t = n.addSecs( -15*60*60 ); // t == 23:00:00
See also addMSecs(), secsTo() and QDateTime::addSecs().
QTime QTime::currentTime () [static]
Returns the current time, as reported by the system clock.
Note that the accuracy depends on the accuracy of the
underlying operating system; not all systems provide
1-millisecond accuracy.
int QTime::elapsed ()
Returns the number of milliseconds that have elapsed since
the last time start() or restart() was called.
Note that the counter wraps to zero 24 hours after the
last call to start() or restart.
Note that the accuracy depends on the accuracy of the
underlying operating system; not all systems provide
1-millisecond accuracy.
Warning: If the system's clock setting has been changed
since the last time start() or restart() was called, the
result is undefined. This can happen e.g. when daylight
saving is turned on or off.
See also start() and restart().
int QTime::hour () const
Returns the hour part (0..23) of the time.
bool QTime::isNull () const
Returns TRUE if the time is equal to 00:00:00.000. A null
time is valid.
See also isValid().
bool QTime::isValid () const
Returns TRUE if the time is valid, or FALSE if the time is
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QTime(3qt)QTime(3qt)
invalid. The time 23:30:55.746 is valid, while 24:12:30 is
invalid.
See also isNull().
bool QTime::isValid ( int h, int m, int s, int ms=0 ) [static]
Returns TRUE if the specified time is valid, otherwise
FALSE.
The time is valid if h is in the range 0-23, m and s are
in the range 0-59, and ms is in the range 0-999.
Example:
QTime::isValid(21, 10, 30); // returns TRUE
QTime::isValid(22, 5, 62); // returns FALSE
int QTime::minute () const
Returns the minute part (0..59) of the time.
int QTime::msec () const
Returns the millisecond part (0..999) of the time.
int QTime::msecsTo ( const QTime & t ) const
Returns the number of milliseconds from this time to t
(which is negative if t is earlier than this time).
Since QTime measures time within a day and there are
86400000 milliseconds in a day, the result is between
-86400000 and 86400000.
See also secsTo().
bool QTime::operator!= ( const QTime & t ) const
Returns TRUE if this time is different from t, or FALSE if
they are equal.
bool QTime::operator<; ( const QTime & t ) const
Returns TRUE if this time is earlier than t, otherwise
FALSE.
bool QTime::operator<;= ( const QTime & t ) const
Returns TRUE if this time is earlier than or equal to t,
otherwise FALSE.
bool QTime::operator== ( const QTime & t ) const
Returns TRUE if this time is equal to t, or FALSE if they
are different.
bool QTime::operator> ( const QTime & t ) const
Returns TRUE if this time is later than t, otherwise
FALSE.
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QTime(3qt)QTime(3qt)bool QTime::operator>= ( const QTime & t ) const
Returns TRUE if this time is later than or equal to t,
otherwise FALSE.
int QTime::restart ()
Sets this time to the current time, and returns the number
of milliseconds that have elapsed since the last time
start() or restart() was called.
This function is guaranteed to be atomic, and is thus very
handy for repeated measurements: call start() to start the
first measurement, then restart() for each later
measurement.
Note that the counter wraps to zero 24 hours after the
last call to start() or restart().
Warning: If the system's clock setting has been changed
since the last time start() or restart() was called, the
result is undefined. This can happen e.g. when daylight
saving is turned on or off.
See also start(), elapsed() and currentTime().
int QTime::second () const
Returns the second part (0..59) of the time.
int QTime::secsTo ( const QTime & t ) const
Returns the number of seconds from this time to t (which
is negative if t is earlier than this time).
Since QTime measures time within a day and there are 86400
seconds in a day, the result is between -86400 and 86400.
See also addSecs() and QDateTime::secsTo().
bool QTime::setHMS ( int h, int m, int s, int ms=0 )
Sets the time to hour h, minute m, seconds s and
milliseconds ms.
h must be in the range 0-23, m and s must be in the range
0-59, and ms must be in the range 0-999. Returns TRUE if
the set time is valid, otherwise FALSE.
See also isValid().
void QTime::start ()
Sets this time to the current time. This is practical for
timing:
QTime t;
t.start(); // start clock
... // some lengthy task
qDebug( "%d\n", t.elapsed() ); // prints # msecs elapsed
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QTime(3qt)QTime(3qt)
See also restart(), elapsed() and currentTime().
QString QTime::toString () const
Returns the time of this object in a textual format.
Milliseconds are not included. The string format is
HH:MM:SS, e.g. 1 second before midnight would be
"23:59:59".
RELATED FUNCTION DOCUMENTATIONQDataStream & operator>> (QDataStream & s, QTime & t)
Reads a time from the stream.
See also Format of the QDataStream operators
QDataStream & operator<;< (QDataStream & s, const QTime & t)
Writes a time to the stream.
See also Format of the QDataStream operators
SEE ALSO
http://doc.trolltech.com/qtime.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
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http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qtime.3qt) and
the Qt version (2.3.1).
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