ios - Share validation code among different UITextFields -

maybe it's simple question can't figure out right way it.

i have uitextfield. since need validate text inserted within text field, i'm using uitextfielddelegate method - (bool)textfield:(uitextfield *)textfield shouldchangecharactersinrange:(nsrange)range replacementstring:(nsstring *)string following:

- (bool)textfield:(uitextfield *)textfield shouldchangecharactersinrange:(nsrange)range replacementstring:(nsstring *)string {    // validation here    // return yes or no depending on previous validation } 

since have text fields (they not belong same controller validation performed) , don't want duplicate text fields validation code, how can achieve elegant way centralize similar validation? don't know if subclassing right way, in case need use same delegation method (the 1 listed above) in different parts of same app.

thank in advance.

this depends on how information validation code requires. if arguments of textfield:shouldchangecharactersinrange:replacementstring: need determine whether return yes or no, can use same delegate textfields.

if need track , store information previous validations in order make validation decisions, easiest way package state object, , have array of objects, each corresponding specific uitextfield. then, in textfield:shouldchangecharactersinrange:replacementstring: use state corresponding textfield passed in.