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


func CFTimeZoneIsDaylightSavingTime(_ tz: CFTimeZone!, _ at: CFAbsoluteTime) -> Bool



The time zone to analyze.


The date in tz to test for daylight savings.

Return Value

true if tz is in daylight savings time at at, otherwise false.

See Also

Getting Daylight Savings Time Information

func CFTimeZoneGetDaylightSavingTimeOffset(CFTimeZone!, CFAbsoluteTime) -> CFTimeInterval

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

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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