The unique ID for this record. It’s guaranteed never to change, no matter how much the record changes. If you need to store a reference to a record, use this value. Type: kABStringProperty.
Available in Mac OS X v10.2 and later.
Declaration Syntax Version Information- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)