Returns a date object initialized relative to 00:00:00 UTC on 1 January 2001 by a given number of seconds.
- iOS 2.0+
- macOS 10.0+
- tvOS 9.0+
- watchOS 2.0+
The number of seconds to add to the reference date (00:00:00 UTC on 1 January 2001). A negative value means the receiver will be earlier than the reference date.
NSDate object initialized relative to the absolute reference date by
This method is a designated initializer for the
NSDate class and is declared primarily for the use of subclasses of
NSDate. When you subclass
NSDate to create a concrete date class, you must override this method.