QTimeZone

The QTimeZone class converts between UTC and local time in a specific time zone. More…

Inheritance diagram of PySide2.QtCore.QTimeZone

Synopsis

Functions

Static functions

Detailed Description

This class provides a stateless calculator for time zone conversions between UTC and the local time in a specific time zone. By default it uses the host system time zone data to perform these conversions.

This class is primarily designed for use in QDateTime ; most applications will not need to access this class directly and should instead use QDateTime with a TimeSpec of TimeZone .

Note

For consistency with QDateTime , QTimeZone does not account for leap seconds.

Remarks

IANA Time Zone IDs

QTimeZone uses the IANA time zone IDs as defined in the IANA Time Zone Database (http://www.iana.org/time-zones). This is to ensure a standard ID across all supported platforms. Most platforms support the IANA IDs and the IANA Database natively, but for Windows a mapping is required to the native IDs. See below for more details.

The IANA IDs can and do change on a regular basis, and can vary depending on how recently the host system data was updated. As such you cannot rely on any given ID existing on any host system. You must use availableTimeZoneIds() to determine what IANA IDs are available.

The IANA IDs and database are also know as the Olson IDs and database, named after their creator.

UTC Offset Time Zones

A default UTC time zone backend is provided which is always guaranteed to be available. This provides a set of generic Offset From UTC time zones in the range UTC-14:00 to UTC+14:00. These time zones can be created using either the standard ISO format names “UTC+00:00” as listed by availableTimeZoneIds() , or using the number of offset seconds.

Windows Time Zones

Windows native time zone support is severely limited compared to the standard IANA TZ Database. Windows time zones cover larger geographic areas and are thus less accurate in their conversions. They also do not support as much historic conversion data and so may only be accurate for the current year.

QTimeZone uses a conversion table derived form the Unicode CLDR data to map between IANA IDs and Windows IDs. Depending on your version of Windows and Qt, this table may not be able to provide a valid conversion, in which “UTC” will be returned.

QTimeZone provides a public API to use this conversion table. The Windows ID used is the Windows Registry Key for the time zone which is also the MS Exchange EWS ID as well, but is different to the Time Zone Name (TZID) and COD code used by MS Exchange in versions before 2007.

System Time Zone

QTimeZone does not support any concept of a system or default time zone. If you require a QDateTime that uses the current system time zone at any given moment then you should use a TimeSpec of LocalTime .

The method systemTimeZoneId() returns the current system IANA time zone ID which on Unix-like systems will always be correct. On Windows this ID is translated from the Windows system ID using an internal translation table and the user’s selected country. As a consequence there is a small chance any Windows install may have IDs not known by Qt, in which case “UTC” will be returned.

Creating a new QTimeZone instance using the system time zone ID will only produce a fixed named copy of the time zone, it will not change if the system time zone changes.

Time Zone Offsets

The difference between UTC and the local time in a time zone is expressed as an offset in seconds from UTC, i.e. the number of seconds to add to UTC to obtain the local time. The total offset is comprised of two component parts, the standard time offset and the daylight-saving time offset. The standard time offset is the number of seconds to add to UTC to obtain standard time in the time zone. The daylight-saving time offset is the number of seconds to add to the standard time offset to obtain daylight-saving time (abbreviated DST and sometimes called “daylight time” or “summer time”) in the time zone.

Note that the standard and DST offsets for a time zone may change over time as countries have changed DST laws or even their standard time offset.

License

This class includes data obtained from the CLDR data files under the terms of the Unicode Data Files and Software License. See Unicode Common Locale Data Repository (CLDR) for details.

See also

QDateTime

class PySide2.QtCore.QTimeZone

PySide2.QtCore.QTimeZone(ianaId)

PySide2.QtCore.QTimeZone(zoneId, offsetSeconds, name, abbreviation[, country=QLocale.AnyCountry[, comment=””]])

PySide2.QtCore.QTimeZone(other)

PySide2.QtCore.QTimeZone(offsetSeconds)

param name:

str

param abbreviation:

str

param comment:

str

param other:

PySide2.QtCore.QTimeZone

param country:

Country

param zoneId:

PySide2.QtCore.QByteArray

param ianaId:

PySide2.QtCore.QByteArray

param offsetSeconds:

int

Create a null/invalid time zone instance.

Creates a custom time zone with an ID of ianaId and an offset from UTC of offsetSeconds . The name will be the name used by displayName() for the LongName , the abbreviation will be used by displayName() for the ShortName and by abbreviation() , and the optional country will be used by country() . The comment is an optional note that may be displayed in a GUI to assist users in selecting a time zone.

The ianaId must not be one of the available system IDs returned by availableTimeZoneIds() . The offsetSeconds from UTC must be in the range -14 hours to +14 hours.

If the custom time zone does not have a specific country then set it to the default value of AnyCountry .

Creates an instance of a time zone with the requested Offset from UTC of offsetSeconds .

The offsetSeconds from UTC must be in the range -14 hours to +14 hours otherwise an invalid time zone will be returned.

PySide2.QtCore.QTimeZone.TimeType

The type of time zone time, for example when requesting the name. In time zones that do not apply DST, all three values may return the same result.

Constant

Description

QTimeZone.StandardTime

The standard time in a time zone, i.e. when Daylight-Saving is not in effect. For example when formatting a display name this will show something like “Pacific Standard Time”.

QTimeZone.DaylightTime

A time when Daylight-Saving is in effect. For example when formatting a display name this will show something like “Pacific daylight-saving time”.

QTimeZone.GenericTime

A time which is not specifically Standard or Daylight-Saving time, either an unknown time or a neutral form. For example when formatting a display name this will show something like “Pacific Time”.
PySide2.QtCore.QTimeZone.NameType

The type of time zone name.

Constant

Description

QTimeZone.DefaultName

The default form of the time zone name, e.g. , or

QTimeZone.LongName

The long form of the time zone name, e.g. “Central European Time”

QTimeZone.ShortName

The short form of the time zone name, usually an abbreviation, e.g. “CET”

QTimeZone.OffsetName

The standard ISO offset form of the time zone name, e.g. “UTC+01:00”
PySide2.QtCore.QTimeZone.abbreviation(atDateTime)
Parameters:

atDateTime – PySide2.QtCore.QDateTime

Return type:

str

Returns the time zone abbreviation at the given atDateTime . The abbreviation may change depending on DST or even historical events.

Note that the abbreviation is not guaranteed to be unique to this time zone and should not be used in place of the ID or display name.

See also

displayName()

static PySide2.QtCore.QTimeZone.availableTimeZoneIds()
Return type:

Returns a list of all available IANA time zone IDs on this system.

See also

isTimeZoneIdAvailable()

static PySide2.QtCore.QTimeZone.availableTimeZoneIds(country)
Parameters:

country – Country

Return type:

Returns a list of all available IANA time zone IDs for a given country .

As a special case, a country of Qt::AnyCountry returns those time zones that do not have any country related to them, such as UTC. If you require a list of all time zone IDs for all countries then use the standard availableTimeZoneIds() method.

See also

isTimeZoneIdAvailable()

static PySide2.QtCore.QTimeZone.availableTimeZoneIds(offsetSeconds)
Parameters:

offsetSeconds – int

Return type:

Returns a list of all available IANA time zone IDs with a given standard time offset of offsetSeconds .

See also

isTimeZoneIdAvailable()

PySide2.QtCore.QTimeZone.comment()
Return type:

str

Returns any comment for the time zone.

A comment may be provided by the host platform to assist users in choosing the correct time zone. Depending on the platform this may not be localized.

PySide2.QtCore.QTimeZone.country()
Return type:

Country

Returns the country for the time zone.

PySide2.QtCore.QTimeZone.daylightTimeOffset(atDateTime)
Parameters:

atDateTime – PySide2.QtCore.QDateTime

Return type:

int

Returns the daylight-saving time offset at the given atDateTime , i.e. the number of seconds to add to the standard time offset to obtain the local daylight-saving time.

For example, for the time zone “Europe/Berlin” the DST offset is +3600 seconds. During standard time will return 0, and when daylight-saving is in effect it will return +3600.

See also

offsetFromUtc() standardTimeOffset()

PySide2.QtCore.QTimeZone.displayName(timeType[, nameType=QTimeZone.DefaultName[, locale=QLocale()]])
Parameters:
Return type:

str

PySide2.QtCore.QTimeZone.displayName(atDateTime[, nameType=QTimeZone.DefaultName[, locale=QLocale()]])
Parameters:
Return type:

str

PySide2.QtCore.QTimeZone.hasDaylightTime()
Return type:

bool

Returns true if the time zone has practiced daylight-saving at any time.

See also

isDaylightTime() daylightTimeOffset()

PySide2.QtCore.QTimeZone.hasTransitions()
Return type:

bool

Returns true if the system backend supports obtaining transitions.

Transitions are changes in the time-zone: these happen when DST turns on or off and when authorities alter the offsets for the time-zone.

See also

nextTransition() previousTransition() transitions()

static PySide2.QtCore.QTimeZone.ianaIdToWindowsId(ianaId)
Parameters:

ianaId – PySide2.QtCore.QByteArray

Return type:

PySide2.QtCore.QByteArray

Returns the Windows ID equivalent to the given ianaId .

See also

windowsIdToDefaultIanaId() windowsIdToIanaIds()

PySide2.QtCore.QTimeZone.id()
Return type:

PySide2.QtCore.QByteArray

Returns the IANA ID for the time zone.

IANA IDs are used on all platforms. On Windows these are translated from the Windows ID into the closest IANA ID for the time zone and country.

PySide2.QtCore.QTimeZone.isDaylightTime(atDateTime)
Parameters:

atDateTime – PySide2.QtCore.QDateTime

Return type:

bool

Returns true if daylight-saving was in effect at the given atDateTime .

See also

hasDaylightTime() daylightTimeOffset()

static PySide2.QtCore.QTimeZone.isTimeZoneIdAvailable(ianaId)
Parameters:

ianaId – PySide2.QtCore.QByteArray

Return type:

bool

Returns true if a given time zone ianaId is available on this system.

See also

availableTimeZoneIds()

PySide2.QtCore.QTimeZone.isValid()
Return type:

bool

Returns true if this time zone is valid.

PySide2.QtCore.QTimeZone.nextTransition(afterDateTime)
Parameters:

afterDateTime – PySide2.QtCore.QDateTime

Return type:

PySide2.QtCore.QTimeZone.OffsetData

Returns the first time zone Transition after the given afterDateTime . This is most useful when you have a Transition time and wish to find the Transition after it.

If there is no transition after the given afterDateTime then an invalid OffsetData will be returned with an invalid QDateTime .

The given afterDateTime is exclusive.

See also

hasTransitions() previousTransition() transitions()

PySide2.QtCore.QTimeZone.offsetData(forDateTime)
Parameters:

forDateTime – PySide2.QtCore.QDateTime

Return type:

PySide2.QtCore.QTimeZone.OffsetData

Returns the effective offset details at the given forDateTime . This is the equivalent of calling offsetFromUtc() , abbreviation() , etc individually but is more efficient.

See also

offsetFromUtc() standardTimeOffset() daylightTimeOffset() abbreviation()

PySide2.QtCore.QTimeZone.offsetFromUtc(atDateTime)
Parameters:

atDateTime – PySide2.QtCore.QDateTime

Return type:

int

Returns the total effective offset at the given atDateTime , i.e. the number of seconds to add to UTC to obtain the local time. This includes any DST offset that may be in effect, i.e. it is the sum of standardTimeOffset() and daylightTimeOffset() for the given datetime.

For example, for the time zone “Europe/Berlin” the standard time offset is +3600 seconds and the DST offset is +3600 seconds. During standard time will return +3600 (UTC+01:00), and during DST it will return +7200 (UTC+02:00).

See also

standardTimeOffset() daylightTimeOffset()

PySide2.QtCore.QTimeZone.__ne__(other)
Parameters:

other – PySide2.QtCore.QTimeZone

Return type:

bool

Returns true if this time zone is not equal to the other time zone.

PySide2.QtCore.QTimeZone.__eq__(other)
Parameters:

other – PySide2.QtCore.QTimeZone

Return type:

bool

Returns true if this time zone is equal to the other time zone.

PySide2.QtCore.QTimeZone.previousTransition(beforeDateTime)
Parameters:

beforeDateTime – PySide2.QtCore.QDateTime

Return type:

PySide2.QtCore.QTimeZone.OffsetData

Returns the first time zone Transition before the given beforeDateTime . This is most useful when you have a Transition time and wish to find the Transition before it.

If there is no transition before the given beforeDateTime then an invalid OffsetData will be returned with an invalid QDateTime .

The given beforeDateTime is exclusive.

See also

hasTransitions() nextTransition() transitions()

PySide2.QtCore.QTimeZone.standardTimeOffset(atDateTime)
Parameters:

atDateTime – PySide2.QtCore.QDateTime

Return type:

int

Returns the standard time offset at the given atDateTime , i.e. the number of seconds to add to UTC to obtain the local Standard Time. This excludes any DST offset that may be in effect.

For example, for the time zone “Europe/Berlin” the standard time offset is +3600 seconds. During both standard and DST offsetFromUtc() will return +3600 (UTC+01:00).

See also

offsetFromUtc() daylightTimeOffset()

PySide2.QtCore.QTimeZone.swap(other)
Parameters:

other – PySide2.QtCore.QTimeZone

Swaps this time zone instance with other . This function is very fast and never fails.

static PySide2.QtCore.QTimeZone.systemTimeZone()
Return type:

PySide2.QtCore.QTimeZone

Returns a QTimeZone object that refers to the local system time, as specified by systemTimeZoneId() .

See also

utc()

static PySide2.QtCore.QTimeZone.systemTimeZoneId()
Return type:

PySide2.QtCore.QByteArray

Returns the current system time zone IANA ID.

On Windows this ID is translated from the Windows ID using an internal translation table and the user’s selected country. As a consequence there is a small chance any Windows install may have IDs not known by Qt, in which case “UTC” will be returned.

PySide2.QtCore.QTimeZone.transitions(fromDateTime, toDateTime)
Parameters:
Return type:

Returns a list of all time zone transitions between the given datetimes.

The given fromDateTime and toDateTime are inclusive.

See also

hasTransitions() nextTransition() previousTransition()

static PySide2.QtCore.QTimeZone.utc()
Return type:

PySide2.QtCore.QTimeZone

Returns a QTimeZone object that refers to UTC (Universal Time Coordinated).

See also

systemTimeZone()

static PySide2.QtCore.QTimeZone.windowsIdToDefaultIanaId(windowsId)
Parameters:

windowsId – PySide2.QtCore.QByteArray

Return type:

PySide2.QtCore.QByteArray

Returns the default IANA ID for a given windowsId .

Because a Windows ID can cover several IANA IDs in several different countries, this function returns the most frequently used IANA ID with no regard for the country and should thus be used with care. It is usually best to request the default for a specific country.

See also

ianaIdToWindowsId() windowsIdToIanaIds()

static PySide2.QtCore.QTimeZone.windowsIdToDefaultIanaId(windowsId, country)
Parameters:
Return type:

PySide2.QtCore.QByteArray

Returns the default IANA ID for a given windowsId and country .

Because a Windows ID can cover several IANA IDs within a given country, the most frequently used IANA ID in that country is returned.

As a special case, AnyCountry returns the default of those IANA IDs that do not have any specific country.

See also

ianaIdToWindowsId() windowsIdToIanaIds()

static PySide2.QtCore.QTimeZone.windowsIdToIanaIds(windowsId)
Parameters:

windowsId – PySide2.QtCore.QByteArray

Return type:

Returns all the IANA IDs for a given windowsId .

The returned list is sorted alphabetically.

See also

ianaIdToWindowsId() windowsIdToDefaultIanaId()

static PySide2.QtCore.QTimeZone.windowsIdToIanaIds(windowsId, country)
Parameters:
Return type:

Returns all the IANA IDs for a given windowsId and country .

As a special case AnyCountry returns those IANA IDs that do not have any specific country.

The returned list is in order of frequency of usage, i.e. larger zones within a country are listed first.

See also

ianaIdToWindowsId() windowsIdToDefaultIanaId()