Returns the daylight saving time offset for a time zone at a given time.


func CFTimeZoneGetDaylightSavingTimeOffset(_ tz: CFTimeZone!, _ at: CFAbsoluteTime) -> CFTimeInterval



The time zone to analyze.


The time in tz to test for daylight saving time offset.

Return Value

The daylight saving time offset for tz at at.

See Also

Getting Daylight Savings Time Information

func CFTimeZoneIsDaylightSavingTime(CFTimeZone!, CFAbsoluteTime) -> Bool

Returns whether or not a time zone is in daylight savings time at a specified date.

func CFTimeZoneGetNextDaylightSavingTimeTransition(CFTimeZone!, CFAbsoluteTime) -> CFAbsoluteTime

Returns the time in a given time zone of the next daylight saving time transition after a given time.

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