# xpc_dictionary_apply(_:_:) Invokes the specified block for every key-value pair in the dictionary. ``` func xpc_dictionary_apply(_ xdict: xpc_object_t, _ applier: (UnsafePointer, xpc_object_t) -> Bool) -> Bool ``` ## Parameters `xdict` The dictionary object which is to be examined. `applier` The block which this function applies to every key/value pair in the dictionary. ## Return Value A Boolean indicating whether iteration of the dictionary completed successfully. Iteration will only fail if the applier block returns false. ## Discussion You should not modify a dictionary’s contents during iteration. There is no guaranteed order of iteration over dictionaries. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)