Sets a temporary resource value on the URL.
- iOS 4.0+
- macOS 10.6+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
The key where the value should be stored. This key must be unique and must not conflict with any system-defined keys. Reverse-domain-name notation is recommended.
The value to store.
Your app can use a temporary resource value to temporarily store a value for an app-defined resource value key in memory without modifying the actual resource that the URL represents. Once set, you can copy the temporary resource value from the URL object just as you would copy system-defined keys—by calling
This method is applicable only to URLs for file system resources.