Description:

This class provides an interface into the system's clock values. In contrast to values of sibling class Ticks, the underlying system timer is not guaranteed to be steady. This means that an object created or set at a later point in time of the program execution, might represent an earlier point in time. This might happen when the system clock gets adjusted in-between two measurements.

Therefore, the class is to be used to represent calendar clock values which usually get converted to human-readable formats (calendar dates and 24/60/60 clock times).

Apart from a few system-dependent conversion methods, the class has no specific interface, but the methods and operators inherited from base TimePointBase.

To construct an object of this type using calendrical date and time values, helper-class CalendarDateTime with its constructor CalendarDateTime(int,int,int,int,int,int,int) is available in case module ALib Strings is included in the ALib Build. A typical construction with this helper could look like this:

 DateTime myDate= CalendarDateTime(2025,1,31,14,5).Get( Timezone::UTC );

See also: For this class, a pretty printer for the GNU debugger is provided.

Definition at line 36 of file datetime.inl.

Inheritance diagram for alib::time::DateTime:

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Collaboration diagram for alib::time::DateTime:

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Public Static Method Index:
static DateTime	FromEpochSeconds (time_t epochSeconds)

static ALIB_DLL DateTime	FromFileTime (const FILETIME &fileTime)

static ALIB_DLL DateTime	FromFileTime (const ULARGE_INTEGER &fileTime)

static ALIB_DLL DateTime	FromSystemTime (const SYSTEMTIME &systemTime, lang::Timezone timezone=lang::Timezone::Local)

Public Static Method Index: inherited from alib::time::TimePointBase< std::chrono::system_clock, DateTime >
static DateTime	BeginningOfEpoch ()

static DateTime	EndOfEpoch ()

static DateTime	FromRaw (TRaw raw)

static DateTime	Now ()

Public Method Index:
time_t	InEpochSeconds () const

bool	operator!= (const DateTime &other) const

bool	operator< (const DateTime &other) const

bool	operator<= (const DateTime &other) const

bool	operator== (const DateTime &other) const

bool	operator> (const DateTime &other) const

bool	operator>= (const DateTime &other) const

ALIB_DLL FILETIME	ToFileTime () const

ALIB_DLL ULARGE_INTEGER	ToFileTimeLI () const

ALIB_DLL SYSTEMTIME	ToSystemTime (lang::Timezone timezone=lang::Timezone::Local) const

Public Method Index: inherited from alib::time::TimePointBase< std::chrono::system_clock, DateTime >
constexpr	TimePointBase (const lang::Initialization init=lang::Initialization::Default)

constexpr	TimePointBase (TTimePoint internalValue)

Duration	Age () const

TTimePoint	Export () const

void	Import (TTimePoint timePoint)

bool	IsOlderThan (const Duration &timeSpan) const

bool	IsSet ()

DateTime	operator+ (const Duration &timeSpan) const

DateTime	operator+ (const typename Duration::TDuration &timeSpan) const

DateTime	operator+= (const Duration &timeSpan)

DateTime	operator+= (const typename Duration::TDuration &timeSpan)

Duration	operator- (const DateTime &other) const

DateTime	operator- (const Duration &timeSpan) const

DateTime	operator- (const typename Duration::TDuration &timeSpan) const

DateTime	operator-= (const Duration &timeSpan)

DateTime	operator-= (const typename Duration::TDuration &timeSpan)

DateTime &	Reset ()

void	SetAs (const DateTime &other)

void	SetFromRaw (TRaw raw)

Duration	Since (const DateTime &other) const

TRaw	ToRaw () const

void	Unset ()

Additional Inherited Members
Public Type Index: inherited from alib::time::TimePointBase< std::chrono::system_clock, DateTime >
using	TRaw
	Integral type used for exporting and importing values in raw units.

using	TTimePoint
	The internal c++ type for time points.

Protected Field Index: inherited from alib::time::TimePointBase< std::chrono::system_clock, DateTime >
TTimePoint	stamp

Method Details:

◆ FromEpochSeconds()

DateTime alib::time::DateTime::FromEpochSeconds ( time_t epochSeconds )

inlinestatic

Static method that creates a DateTime object representing the given system point in time measured in seconds since January 1st 1970, 00:00:00 GMT.

Parameters

epochSeconds The milliseconds in the epoch to convert.

Returns: A time stamp object

Definition at line 70 of file datetime.inl.

◆ FromFileTime() [1/2]

ALIB_DLL DateTime alib::time::DateTime::FromFileTime ( const FILETIME & fileTime )

static

Static method that creates a DateTime object representing the given "file time". File time is a 64-bit value that represents the number of 100 nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 UTC.

Note: Microsoft Windows specific.

Parameters

fileTime The file time to use.

Returns: A time stamp object

◆ FromFileTime() [2/2]

ALIB_DLL DateTime alib::time::DateTime::FromFileTime ( const ULARGE_INTEGER & fileTime )

static

Static method that creates a DateTime object representing the given "file time". File time is a 64-bit value that represents the number of 100 nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 UTC.

Note: Microsoft Windows specific.

Parameters

fileTime The file time to use.

Returns: A time stamp object

◆ FromSystemTime()

ALIB_DLL DateTime alib::time::DateTime::FromSystemTime	(	const SYSTEMTIME &	systemTime,
		lang::Timezone	timezone = lang::Timezone::Local )

static

Static method that creates a DateTime object representing the given as windows system time.

Note: Microsoft Windows specific.

Parameters

systemTime	Pointer to a SYSTEMTIME struct that holds the system time to use.
timezone	Denote if the time is interpreted as local or UTC. Defaults to `TimeZone::Local`.

Returns: Seconds in the epoch.

◆ InEpochSeconds()

time_t alib::time::DateTime::InEpochSeconds ( ) const

inline

Converts the internal value into seconds since January 1, 1970, 00:00:00 GMT. The conversion is dependent on time zone and system clock setting of the host.

Returns: Seconds in the epoch.

Definition at line 56 of file datetime.inl.

◆ operator!=()

bool alib::time::DateTime::operator!= ( const DateTime & other ) const

inline

Not equal to operator.

Parameters

other The time stamp to compare.

Returns: The result of the comparison.

Definition at line 175 of file datetime.inl.

◆ operator<()

bool alib::time::DateTime::operator< ( const DateTime & other ) const

inline

Less than operator.

Parameters

other The time stamp to compare.

Returns: A reference to this object.

Definition at line 185 of file datetime.inl.

◆ operator<=()

bool alib::time::DateTime::operator<= ( const DateTime & other ) const

inline

Less than or equal to operator.

Parameters

other The time stamp to compare.

Returns: The result of the comparison.

Definition at line 195 of file datetime.inl.

◆ operator==()

bool alib::time::DateTime::operator== ( const DateTime & other ) const

inline

Equal to operator.

Parameters

other The time stamp to compare.

Returns: The result of the comparison.

Definition at line 164 of file datetime.inl.

◆ operator>()

bool alib::time::DateTime::operator> ( const DateTime & other ) const

inline

Greater than operator.

Parameters

other The time stamp to compare.

Returns: The result of the comparison.

Definition at line 205 of file datetime.inl.

◆ operator>=()

bool alib::time::DateTime::operator>= ( const DateTime & other ) const

inline

Greater than or equal to operator.

Parameters

other The time stamp to compare.

Returns: The result of the comparison.

Definition at line 215 of file datetime.inl.

◆ ToFileTime()

ALIB_DLL FILETIME alib::time::DateTime::ToFileTime ( ) const

Converts the internal value into windows specific file time, a 64-bit value that represents the number of 100 nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 UTC. The conversion is dependent on time zone and system clock setting of the host.

Note: Microsoft Windows specific.

Returns: The Windows OS file time value represented by this object.

◆ ToFileTimeLI()

ALIB_DLL ULARGE_INTEGER alib::time::DateTime::ToFileTimeLI ( ) const

Converts the internal value into windows specific file time, a 64-bit value that represents the number of 100 nanosecond intervals that have elapsed since 12:00 A.M. January 1, 1601 UTC. The conversion is dependent on time zone and system clock setting of the host.

Note: Microsoft Windows specific.

Returns: The Windows OS file time represented by this object as type struct ULARGE_INTEGER.

◆ ToSystemTime()

ALIB_DLL SYSTEMTIME alib::time::DateTime::ToSystemTime ( lang::Timezone timezone = lang::Timezone::Local ) const

Converts the internal value into windows specific system time struct.

Note: Microsoft Windows specific.

Parameters

timezone Denote if the time that is returned should be local or UTC. Defaults to TimeZone::Local.

Returns: The time point as SYSTEMTIME.

The documentation for this class was generated from the following file:

datetime.inl

Description:

Public Static Method Index:

Public Method Index:

Additional Inherited Members

Method Details:

◆ FromEpochSeconds()

◆ FromFileTime() [1/2]

◆ FromFileTime() [2/2]

◆ FromSystemTime()

◆ InEpochSeconds()

◆ operator!=()

◆ operator<()

◆ operator<=()

◆ operator==()

◆ operator>()

◆ operator>=()

◆ ToFileTime()

◆ ToFileTimeLI()

◆ ToSystemTime()