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# birthday

A date component for the Gregorian birthday of the contact.

```
var birthday: DateComponents? { get set }
```

## Discussion

A Gregorian birthday can be displayed using this property, whose values are the relevant properties of an <doc://com.apple.documentation/documentation/Foundation/NSDateComponents> object. Day and month are required for this property, and year is optional. Calendar can be `nil` or Gregorian. All other date components are invalid.

---

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