---
title: MusicEventUserData
framework: audiotoolbox
role: symbol
role_heading: Structure
path: audiotoolbox/musiceventuserdata
---

# MusicEventUserData

Describes a user-defined event.

## Declaration

```swift
struct MusicEventUserData
```

## Topics

### Initializers

- [init()](audiotoolbox/musiceventuserdata/init().md)
- [init(length:data:)](audiotoolbox/musiceventuserdata/init(length:data:).md)

### Instance Properties

- [data](audiotoolbox/musiceventuserdata/data.md)
- [length](audiotoolbox/musiceventuserdata/length.md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Sendable](swift/sendable.md)

## See Also

### Iterating Over Music Events

- [NewMusicEventIterator(_:_:)](audiotoolbox/newmusiceventiterator(_:_:).md)
- [DisposeMusicEventIterator(_:)](audiotoolbox/disposemusiceventiterator(_:).md)
- [MusicEventIteratorNextEvent(_:)](audiotoolbox/musiceventiteratornextevent(_:).md)
- [MusicEventIteratorSeek(_:_:)](audiotoolbox/musiceventiteratorseek(_:_:).md)
- [MusicEventIteratorDeleteEvent(_:)](audiotoolbox/musiceventiteratordeleteevent(_:).md)
- [MusicEventIteratorGetEventInfo(_:_:_:_:_:)](audiotoolbox/musiceventiteratorgeteventinfo(_:_:_:_:_:).md)
- [MusicEventIteratorHasCurrentEvent(_:_:)](audiotoolbox/musiceventiteratorhascurrentevent(_:_:).md)
- [MusicEventIteratorHasNextEvent(_:_:)](audiotoolbox/musiceventiteratorhasnextevent(_:_:).md)
- [MusicEventIteratorHasPreviousEvent(_:_:)](audiotoolbox/musiceventiteratorhaspreviousevent(_:_:).md)
- [MusicEventIteratorPreviousEvent(_:)](audiotoolbox/musiceventiteratorpreviousevent(_:).md)
- [MusicEventIteratorSetEventInfo(_:_:_:)](audiotoolbox/musiceventiteratorseteventinfo(_:_:_:).md)
- [MusicEventIteratorSetEventTime(_:_:)](audiotoolbox/musiceventiteratorseteventtime(_:_:).md)
- [MusicEventIterator](audiotoolbox/musiceventiterator.md)
- [MusicEventType](audiotoolbox/musiceventtype.md)
- [ExtendedNoteOnEvent](audiotoolbox/extendednoteonevent.md)