---
title: PHPersistentChangeToken
framework: photos
role: symbol
role_heading: Class
path: photos/phpersistentchangetoken
---

# PHPersistentChangeToken

An opaque object that tracks the state of the Photos library between runs, and that you can copy and serialize for future use.

## Declaration

```swift
class PHPersistentChangeToken
```

## Mentioned in

Uploading asset resources in the background

## Topics

### Initializers

- [init(coder:)](photos/phpersistentchangetoken/init(coder:).md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSCoding](foundation/nscoding.md)
- [NSCopying](foundation/nscopying.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [NSSecureCoding](foundation/nssecurecoding.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Fetching Change History

- [fetchPersistentChanges(since:)](photos/phphotolibrary/fetchpersistentchanges(since:).md)
- [PHPersistentChangeFetchResult](photos/phpersistentchangefetchresult.md)
- [currentChangeToken](photos/phphotolibrary/currentchangetoken.md)