[objc] UITextField, textField:shouldChangeCharactersInRange:replacementString:에서 수정후의 문자열 얻기

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

...

    NSString *changedStr = [textField.text stringByReplacingCharactersInRange:range withString:string];

    return YES;

}