code: public function getValidator()
      {
          if (null === $this->validator) {
              $validator = new RegexValidator('/^([\+][0-9]{1,3}[ \.\-])?([\(]{1}[0-9]{1,6}[\)])?([0-9 \.\-\/]{3,20})((x|ext|extension)[ ]?[0-9]{1,4})?$/');
              $validator->setMessage(
                  /*@translate */ 'Please enter a phone Number. You can use the intenational format. Only digits and \'+\'.',
                  RegexValidator::NOT_MATCH
              );
  
              $this->validator = $validator;
          }
  
          return $this->validator;
      }
docs: Get a validator if none has been set.
  https://github.com/posabsolute/jQuery-Validation-Engine/issues/265
  @return RegexValidator