chamilo-lms2/main/inc/lib/formvalidator/Rule/MobilePhoneNumber.php

<?php
/* For licensing terms, see /license.txt */

/**
 * Abstract base class for QuickForm validation rules.
 */

/**
 * Validate telephones.
 */
class HTML_QuickForm_Rule_Mobile_Phone_Number extends HTML_QuickForm_Rule
{
    /**
     * Validates mobile phone number.
     *
     * @param string Mobile phone number to be validated
     * @param string Not using it. Just to respect the declaration
     *
     * @return bool returns true if valid, false otherwise
     */
    public function validate($mobilePhoneNumber, $options = null)
    {
        $rule = "/^\d{11}$/";

        return preg_match($rule, $mobilePhoneNumber);
    }
}