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# eventClass

The event class for the receiver.

```
var eventClass: AEEventClass { get }
```

## Discussion

The event class (a four-character code) for the receiver, or 0 if an error occurs.

The receiver must be an Apple event. An Apple event is identified by its event class and event ID, a pair of four-character codes stored as 32-bit integers. For example, most events in the Standard suite have the four-character code `'core'` (defined as the constant `kAECoreSuite` in `AE.framework`, a subframework of `ApplicationServices.framework`). For more information on event classes and event IDs, see Building an Apple Event in Apple Events Programming Guide.

---

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