Type Property


The time zone currently used by the system.


@property(class, readonly, copy) NSTimeZone *systemTimeZone;


If the current system time zone cannot be determined, the GMT time zone is used instead.

If you access the systemTimeZone class property, its value is cached by the app and doesn't update if the user subsequently changes the system time zone. In order for the systemTimeZone property to reflect the new time zone, you must first call the resetSystemTimeZone method to clear the cached value. Then, the next time you access the systemTimeZone property, it returns the current system time zone, and caches that value.

If you access the systemTimeZone class property, assign its value to a variable, and clear the cached value for the property by calling the resetSystemTimeZone method, the object stored in the variable doesn't update to reflect the new system time zone. Contrast this behavior with that of the localTimeZone class property, which returns a proxy object that always reflects the current system time zone.

See Also

Working with System Time Zones


An object that tracks the current system time zone.

+ resetSystemTimeZone

Clears any time zone value cached for the systemTimeZone property.


The default time zone for the current app.