<?php
namespace PFBC\Validation;

class AlphaNumeric extends RegExp {
    protected $message = "Error: %element% must be alphanumeric (contain only numbers, letters, underscores, and/or hyphens).";

    public function __construct($message = "") {
        parent::__construct("/^[a-zA-Z0-9_-]+$/", $message);
    }
}
