---
title: "enumerator(for:)"
framework: fileprovider
role: symbol
role_heading: Instance Method
path: "fileprovider/nsfileproviderextension/enumerator(for:)"
---

# enumerator(for:)

Returns an enumerator for the specified item.

## Declaration

```swift
func enumerator(for containerItemIdentifier: NSFileProviderItemIdentifier) throws -> any NSFileProviderEnumerator
```

## Parameters

- `containerItemIdentifier`: The persistent identifier for a document or folder.

## Mentioned in

Defining Your File Provider’s Content

## Return Value

Return Value An enumerator for the specified document or folder, or nil in Objective-C if an error has occurred.

## Discussion

Discussion Your File Provider extension must define one or more classes that adopt the NSFileProviderEnumerator protocol. Instances of these classes must be able to enumerate both the contents of the specified item and any changes to the content. Override this method to return an instance of your custom NSFileProviderEnumerator class for the specified item (either a document or a folder). For more information, see Content and Change Tracking.

## See Also

### Working with items and persistent identifiers

- [persistentIdentifierForItem(at:)](fileprovider/nsfileproviderextension/persistentidentifierforitem(at:).md)
- [urlForItem(withPersistentIdentifier:)](fileprovider/nsfileproviderextension/urlforitem(withpersistentidentifier:).md)
- [item(for:)](fileprovider/nsfileproviderextension/item(for:).md)
- [NSFileProviderItemIdentifier](fileprovider/nsfileprovideritemidentifier.md)