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  "title" : "Resource Loading Request Identifiers"
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# Resource Loading Request Identifiers

Special values for the [`PHAssetResourceDataRequestID`](/documentation/Photos/PHAssetResourceDataRequestID) identifier that are returned by asynchronous requests.

## Topics

### Constants

[`var PHInvalidAssetResourceDataRequestID: PHAssetResourceDataRequestID`](/documentation/Photos/PHInvalidAssetResourceDataRequestID)

The asynchronous resource loading request cannot be canceled.


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