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# data1

Additional data associated with this event.

```
var data1: Int { get }
```

## Discussion

The originator of the event defines the data in this property, and the data is dependent on the event type. If the type of this event isn’t  [`NSAppKitDefined`](/documentation/AppKit/NSAppKitDefined), [`NSSystemDefined`](/documentation/AppKit/NSSystemDefined), [`NSApplicationDefined`](/documentation/AppKit/NSApplicationDefined), or [`NSPeriodic`](/documentation/AppKit/NSPeriodic), accessing this property raises <doc://com.apple.documentation/documentation/Foundation/NSExceptionName/internalInconsistencyException>.

[`NSPeriodic`](/documentation/AppKit/NSPeriodic) events don’t use this property.

## See Also

[`subtype`](/documentation/AppKit/NSEvent/subtype)

The event’s subtype.

[`+  otherEventWithType:location:modifierFlags:timestamp:windowNumber:context:subtype:data1:data2:`](/documentation/AppKit/NSEvent/otherEvent(with:location:modifierFlags:timestamp:windowNumber:context:subtype:data1:data2:))

Creates and returns a new event object that describes a custom event.


---

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