ios - Prons and Cons of using objectForKey and valueForKey? -


as know there difference between objectforkey , valueforkey.

objectforkey: datatype :(id)akey whereas valueforkey: datatype :(nsstring *)key.

i know topic discussed on stackoverflow not provide me satisfaction. please not mark duplicated

i referred :

difference between objectforkey , valueforkey?

what difference between valueforkey:, objectforkey:, , valueforkeypath:?

finally nsstring type of id. why apple provide valueforkey on objectforkey. think there performance problem or other. question if objectforkey satisfied requirement of valueforkey need of valueforkey?


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