---
title: identifier
framework: usernotifications
role: symbol
role_heading: Instance Property
path: usernotifications/unnotificationcategory/identifier
---

# identifier

The unique string assigned to the category.

## Declaration

```swift
var identifier: String { get }
```

## Mentioned in

Declaring your actionable notification types Generating a remote notification

## Discussion

Discussion Use this string to differentiate the different types of notifications that your app can send. To assign a category to a local notification, assign this string to the categoryIdentifier property of the content object. To assign a category to a remote notification, use the string as the value of the category key in the notification payload aps dictionary.

## See Also

### Getting the Information

- [actions](usernotifications/unnotificationcategory/actions.md)
- [intentIdentifiers](usernotifications/unnotificationcategory/intentidentifiers.md)
- [hiddenPreviewsBodyPlaceholder](usernotifications/unnotificationcategory/hiddenpreviewsbodyplaceholder.md)
- [categorySummaryFormat](usernotifications/unnotificationcategory/categorysummaryformat.md)