Parakeety's Blog

#TODO equal identical NSObject isEqual Container class: deep comparison overriding isEqual isEqualClassName call isEqualClassName in isEqual override hash if isEqual: determines that two objects are equal, they must have the same hash value NSString *a = @"a"; NSString *b = @"b"; a == b is true use isequaltoString never use == for comparing strings. string interning 参考記事 http://nshipster.com/equality/ https://developer.apple.com/library/ios/documentation/general/conceptual/DevPedia-CocoaCore/ObjectComparison.html