Predefined date and time format styles.
- Core Foundation
The format for these date and time styles is not exact because they depend on the locale, user preference settings, and the operating system version. Do not use these constants if you want an exact format, for example if you are parsing an external data file which contains date information in a fixed format. There are several different “lengths” of the formats:
"long" era names, for example "Anno Domini" instead of "AD"
"very short" names for months and weekdays; for example, "F" instead of "Friday"
"standalone" names for months and weekdays (for some locales or languages, a month name displayed in isolation needs to be written differently than a month name within a displayed date)
names of quarters; for example, "Q2" for a short quarter name