Convert to arabic digits

Digit.php

<?php
/**
 * Created by PhpStorm.
 * User: dhassanali
 * Date: 12/4/17
 * Time: 8:56 PM
 */

class Digit
{
    public static function toArabic($str)
    {
        return str_replace(
            ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'],
            ['٠', '١', '٢', '٣', '٤', '٥', '٦', '٧', '٨', '٩'],
            $str
        );
    }

    public static function toEnglish($str)
    {
        return str_replace(
            ['٠', '١', '٢', '٣', '٤', '٥', '٦', '٧', '٨', '٩'],
            ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'],
            $str
        );
    }
}