• Several common protocols in IOS: nscopying / nsmutablecopying


    1. Some explanations When it comes to nscopying and nsmutablecopying protocols, we have to say copy and mutablecopy. If a class wants to support copy operation, it must implement the nscopying protocol, that is, the copywithzone method; If a class wants to support mutablecopy operation, it must implement nsmutablecopying protocol, that is to say, implement […]