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# CFCalendarUnit

CFCalendarUnit constants are used to specify calendrical units, such as day or month, in various calendar calculations.

```
struct CFCalendarUnit
```

## Topics

### Constants

[`era`](/documentation/CoreFoundation/CFCalendarUnit/era)

Specifies the era unit.

[`year`](/documentation/CoreFoundation/CFCalendarUnit/year)

Specifies the year unit.

[`month`](/documentation/CoreFoundation/CFCalendarUnit/month)

Specifies the month unit.

[`day`](/documentation/CoreFoundation/CFCalendarUnit/day)

Specifies the day unit.

[`hour`](/documentation/CoreFoundation/CFCalendarUnit/hour)

Specifies the hour unit.

[`minute`](/documentation/CoreFoundation/CFCalendarUnit/minute)

Specifies the minute unit.

[`second`](/documentation/CoreFoundation/CFCalendarUnit/second)

Specifies the second unit.

[`week`](/documentation/CoreFoundation/CFCalendarUnit/week)

Specifies the week unit.

[`weekday`](/documentation/CoreFoundation/CFCalendarUnit/weekday)

Specifies the weekday unit.

[`weekdayOrdinal`](/documentation/CoreFoundation/CFCalendarUnit/weekdayOrdinal)

Specifies the ordinal weekday unit.

[`quarter`](/documentation/CoreFoundation/CFCalendarUnit/quarter)

Specifies the quarter-year unit.

[`weekOfMonth`](/documentation/CoreFoundation/CFCalendarUnit/weekOfMonth)

Specifies the original week of a month calendar unit.

[`weekOfYear`](/documentation/CoreFoundation/CFCalendarUnit/weekOfYear)

Specifies the original week of the year calendar unit.

[`yearForWeekOfYear`](/documentation/CoreFoundation/CFCalendarUnit/yearForWeekOfYear)

Specifies the relative year for a week within a year calendar unit.


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