Stores time information. More...

Public Methods
constexpr	QTime ()

	QTime (int h, int m, int s=0, int ms=0)

QTime	addMSecs (int msecs) const

QTime	addSecs (int seconds) const

int	elapsed () const

int	hour () const

constexpr bool	isNull () const

bool	isValid () const

int	minute () const

int	msec () const

int	msecsSinceStartOfDay () const

int	msecsTo (const QTime &value) const

bool	operator!= (const QTime &value) const

bool	operator< (const QTime &value) const

bool	operator<= (const QTime &value) const

bool	operator== (const QTime &value) const

bool	operator> (const QTime &value) const

bool	operator>= (const QTime &value) const

int	restart ()

int	second () const

int	secsTo (const QTime &value) const

bool	setHMS (int h, int m, int s, int ms=0)

void	start ()

QString	toString (const QString &format) const

QString	toString (Qt::DateFormat format=Qt::TextDate) const

Static Public Methods
static QTime	currentTime ()

static QTime	fromMSecsSinceStartOfDay (int msecs)

static QTime	fromString (const QString &str, const QString &format)

static QTime	fromString (const QString &str, Qt::DateFormat format=Qt::TextDate)

static bool	isValid (int h, int m, int s, int ms=0)

Friends
QDataStream &	operator<< (QDataStream &stream, const QTime &time)

QDataStream &	operator>> (QDataStream &stream, QTime &time)

class	QDateTime

Detailed Description

The QTime class stores time information which is defined as the number of hours, minutes, seconds, and milliseconds since midnight. This class retrieves the current time from the operating system internal clock. A variety of methods are provided to calculate a time based on some offset or compare two existing times.

A QTime is typically created by specifying the number of hours, minutes, seconds, and milliseconds or using the static method currentTime() which returns a new QTime based on the system clock.

QTime uses a 24 hour clock format and has no concept of AM/PM. This class does not store any information about time zones or daylight saving time (DST).

Methods

The hour(), minute(), second(), and msec() methods provide access to the number of hours, minutes, seconds, and milliseconds of the given QTime. The same information is provided in a text format by calling one of the toString() methods.

There are additional methods which can be used to calculate a span of elapsed time using start(), restart(), and elapsed(). The number of seconds or milliseconds between two times can be found using secsTo() or msecsTo().

See also: QDate, QDateTime

Constructor & Destructor Documentation

constexpr QTime::QTime ( )

inlineconstexpr

Constructs an invalid null QTime.

See also: isNull(), isValid()

QTime::QTime	(	int	h,
		int	m,
		int	s = `0`,
		int	ms = `0`
	)

Constructs a new QTime with hour h, minute m, seconds s and milliseconds ms. The value for h must be in the range 0 to 23, m and s must be in the range 0 to 59, and ms must be in the range 0 to 999.

See also: isValid()

Method Documentation

QTime QTime::addMSecs ( int msecs ) const

nodiscard

Adds the given number of msecs milliseconds to the current QTime and returns the result. If msecs is negative the value for msecs is subtracted from this QTime. The value for QTime will wrap if it crosses midnight.

See also: addSecs(), msecsTo(), QDateTime::addMSecs()

QTime QTime::addSecs ( int seconds ) const

nodiscard

Adds the given number of seconds to the current QTime and returns the result. If seconds is negative the value for seconds is subtracted from this QTime. The value for QTime will wrap if it crosses midnight.

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(), QDateTime::addSecs()

QTime QTime::currentTime ( )

static

Returns the current QTime as reported by the system clock. The accuracy depends on the underlying operating system and not all operating systems provide 1 millisecond accuracy.

int QTime::elapsed ( ) const

Returns the number of milliseconds which has elapsed since the last time start() or restart() was called. The count is reset to zero every 24 hours. If the system clock is modified while this method is tracking a count, the result will be undefined. A problem can also occur if daylight saving time is turned on or off.

QTime QTime::fromMSecsSinceStartOfDay ( int msecs )

inlinestatic

Returns a new QTime with the time set to the number of milliseconds, msecs since midnight. If msecs falls outside the valid range an invalid QTime will be returned.

See also: msecsSinceStartOfDay()

QTime QTime::fromString	(	const QString &	str,
		const QString &	format
	)

static

Returns the QTime represented by the str using the format given. If the string does not represent a valid time using the given format, then QTime will set to an invalid time.

The following expressions can be used as part of the format. If any other characters are used in the format they will be treated as literal text. Any sequence of characters which are enclosed in single quotes will also be treated as literal text.

Expression	Output
h	Hour without a leading zero (0 to 23 or 1 to 12 if AM/PM display)
hh	Hour with a leading zero (00 to 23 or 01 to 12 if AM/PM display)
m	Minute without a leading zero (0 to 59)
mm	Minute with a leading zero (00 to 59)
s	Second without a leading zero (0 to 59)
ss	Second with a leading zero (00 to 59)
z	Milliseconds without leading zeroes (0 to 999)
zzz	Milliseconds with leading zeroes (000 to 999)
AP	AM/PM time, AP must be either "AM" or "PM".
ap	AM/PM time, ap must be either "am" or "pm".

QTime time = QTime::fromString("1mm12car00", "m'mm'hcarss"); // time is 12:01.00

Expressions which do not expect leading zeroes (h, m, s and z) are greedy. This means they will consume two digits even if this produces a number which is outside the range of accepted values. For example, the following string does not mean 00:07:10, because the m will consume two digits, resulting in an invalid time.

QTime time = QTime::fromString("00:710", "hh:ms"); // invalid

Any field which is not represented in the given format will be set to zero.

QTime time = QTime::fromString("1.30", "m.s"); // time is 00:01:30.000

See also: QDate::fromString(), QDate::toString(), QDateTime::fromString()

QTime QTime::fromString	(	const QString &	str,
		Qt::DateFormat	format = `Qt::TextDate`
	)

static

Returns the QTime represented by the str using the format given. If the string does not represent a valid time then QTime will set to an invalid time. This method uses a "C" locale encoded string to convert milliseconds to a float.

int QTime::hour ( ) const

Returns the hour part (0 to 23) of this QTime.

See also: minute(), msec(), second()

constexpr bool QTime::isNull ( ) const

inlineconstexpr

Returns true if this QTime was default constructed, otherwise returns false. A null time is an invalid time.

See also: isValid()

bool QTime::isValid ( ) const

Returns true if the QTime is valid, otherwise returns false. For example, 24:12:30 is not a valid time.

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 returns false. The time is valid if h is in the range 0 to 23, m and s are in the range 0 to 59, and ms is in the range 0 to 999.

QTime::isValid(21, 10, 30); // returns true

QTime::isValid(22, 5, 65); // returns false

int QTime::minute ( ) const

Returns the minute part (0 to 59) of this QTime.

See also: hour(), msec(), second()

int QTime::msec ( ) const

Returns the millisecond part (0 to 999) of this QTime.

See also: hour(), minute(), second()

int QTime::msecsSinceStartOfDay ( ) const

inline

Returns the number of milliseconds since the start of the day, which is 00:00:00.

See also: fromMSecsSinceStartOfDay()

int QTime::msecsTo ( const QTime & value ) const

Returns the number of milliseconds between this QTime and the given value. If value is earlier than this QTime the number of milliseconds returned is negative.

See also: addMSecs(), QDateTime::msecsTo(), secsTo()

bool QTime::operator!= ( const QTime & value ) const

inline

Returns true if this QTime is different from value, otherwise returns false.

bool QTime::operator< ( const QTime & value ) const

inline

Returns true if this QTime is earlier than value, otherwise returns false.

bool QTime::operator<= ( const QTime & value ) const

inline

Returns true if this QTime is earlier than or equal to value, otherwise returns false.

bool QTime::operator== ( const QTime & value ) const

inline

Returns true if this QTime is equal to value, otherwise returns false.

bool QTime::operator> ( const QTime & value ) const

inline

Returns true if this QTime is later than value, otherwise returns false.

bool QTime::operator>= ( const QTime & value ) const

inline

Returns true if this QTime is later than or equal to value, otherwise returns false.

int QTime::restart ( )

Returns the number of milliseconds which has elapsed since the last time start() or restart() was called. The count is reset to zero every 24 hours. If the system clock is modified while this method is tracking a count, the result will be undefined. A problem can also occur if daylight saving time is turned on or off.

Sets this QTime to the current system time.

This method is useful for repeated measurements. Simply call start() to find the first measurement and then restart() for each later measurement.

See also: currentTime(), elapsed()

int QTime::second ( ) const

Returns the second part (0 to 59) of this QTime.

See also: hour(), minute(), msec()

int QTime::secsTo ( const QTime & value ) const

Returns the number of seconds between this QTime and the given value. If value is earlier than this QTime the number of seconds returned is negative.

See also: addSecs(), QDateTime::secsTo()

bool QTime::setHMS	(	int	h,
		int	m,
		int	s,
		int	ms = `0`
	)

Sets this QTime to hour h, minute m, seconds s and milliseconds ms. Returns true if the set time is valid, otherwise returns false. The value for h must be in the range 0 to 23, m and s must be in the range 0 to 59, and ms must be in the range 0 to 999.

See also: isValid()

void QTime::start ( )

Sets this QTime to the current system time.

QTime t;
t.start();
 
doSomeTask();
 
qDebug("Time elapsed: %d ms", t.elapsed());

See also: currentTime(), elapsed(), restart()

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

Returns this QTime as a string. The format determines how the result will be formatted. If the QTime is invalid an empty string will be returned. If format is empty the default format of "hh:mm:" will be is used.

The following expressions can be used as part of the format.

Expression	Output
h	Hour without a leading zero (0 to 23 or 1 to 12 if AM/PM display)
hh	Hour with a leading zero (00 to 23 or 01 to 12 if AM/PM display)
H	Hour without a leading zero (0 to 23, even with AM/PM display)
HH	Hour with a leading zero (00 to 23, even with AM/PM display)
m	Minute without a leading zero (0 to 59)
mm	Minute with a leading zero (00 to 59)
s	Second without a leading zero (0 to 59)
ss	Second with a leading zero (00 to 59)
z	Milliseconds without leading zeroes (0 to 999)
zzz	Milliseconds with leading zeroes (000 to 999)
AP or A	AM/PM display, AP will be replaced by either "AM" or "PM".
ap or a	am/pm display, ap will be replaced by either "am" or "pm".
t	Timezone, for example "CEST"

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 singleq uotes ("''") are replaced by a single quote in the output.

These are example format strings (assuming that the QTime is 14:13:09.042)

Format	Result
hh:mm:ss.zzz	14:13:09.042
h:m:s ap	2:13:9 pm
H:m:s a	14:13:9 pm

See also: QDate::toString(), QDateTime::toString()

QString QTime::toString ( Qt::DateFormat format = Qt::TextDate ) const

Returns this QTime as a string. The format determines how the result will be formatted. If the QTime is invalid an empty string will be returned.

Qt::TextDate: String format is HH:MM:SS
Qt::ISODate: String format is HH:mm:ss
Qt::SystemLocaleShortDate or Qt::SystemLocaleLongDate: String format depends on the locale settings of the system. Equivalent to calling one of the following.
//

QLocale::system().toString(time, QLocale::ShortFormat)

//

QLocale::system().toString(time, QLocale::LongFormat)
Qt::DefaultLocaleShortDate or Qt::DefaultLocaleLongDate: String format depends on the default application locale which is the locale set with QLocale::setDefault() or the system locale if no default has been set. Using this format is equivalent to calling one of the following.
//

QLocale().toString(time, QLocale::ShortFormat)

//

QLocale().toString(time, QLocale::LongFormat)

Friends And Related Function Documentation

QDataStream & operator<<	(	QDataStream &	stream,
		const QTime &	time
	)

friend

Writes the given time to the stream. Returns a reference to the stream.

Refer to Serializing Data Types for additional information.

QDataStream & operator>>	(	QDataStream &	stream,
		QTime &	time
	)

friend

Reads from the stream into the given time. Returns a reference to the stream.

Refer to Serializing Data Types for additional information.

Public Methods

Static Public Methods

Friends

Detailed Description

Methods

Constructor & Destructor Documentation

Method Documentation

Friends And Related Function Documentation