KVC & KVO2018-06-28 本文已影响0人 張小明 https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/KeyValueCoding/index.html https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/KeyValueObserving/KeyValueObserving.html#//apple_ref/doc/uid/10000177i
