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# eventNumber

The counter value of the latest mouse or tracking-rectangle event object.

```
var eventNumber: Int { get }
```

## Discussion

Every system-generated mouse and tracking-rectangle event increments this counter. If you access this property on an event of an unsupported type, AppKit raises <doc://com.apple.documentation/documentation/Foundation/NSExceptionName/internalInconsistencyException>.

## See Also

[`enterExitEvent(with:location:modifierFlags:timestamp:windowNumber:context:eventNumber:trackingNumber:userData:)`](/documentation/AppKit/NSEvent/enterExitEvent(with:location:modifierFlags:timestamp:windowNumber:context:eventNumber:trackingNumber:userData:))

Creates and returns a new event object that describes a tracking-rectangle or cursor-update event.

[`mouseEvent(with:location:modifierFlags:timestamp:windowNumber:context:eventNumber:clickCount:pressure:)`](/documentation/AppKit/NSEvent/mouseEvent(with:location:modifierFlags:timestamp:windowNumber:context:eventNumber:clickCount:pressure:))

Creates and returns a new event object that describes a mouse-down, -up, -moved, or -dragged event.


---

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