komischer fehler in meinem php skript

<?php

/**

 * Looks in the database to see if a record or records exist

 *

 * @param String $string_dbhost - MySQL host.Can be either a host name or an IP address

 * @param String $string_dbusername - MySQL user name

 * @param String $string_dbpassword - MySQL user password

 * @param String $string_dbname - MySQL database name

 * @param Mysqli &$mysqli_link - MySQL link identifier

 * @return Boolean

 **/

function connect_mysqldatabase($string_dbhost, $string_dbusername, $string_dbpassword, $string_dbname, &$mysqli_link) 

{

        $mysqli_link = new mysqli($string_dbhost, $string_dbusername, $string_dbpassword, $string_dbname);

        if (!$mysqli_link) {

                /*echo "Error: Unable to connect to MySQL." . PHP_EOL;

                echo "Debugging errno: " . mysqli_connect_errno() . PHP_EOL;

                echo "Debugging error: " . mysqli_connect_error() . PHP_EOL;

                */

                return false;

        }

        else

        {

                return true;

        }

}

var $mysqli;

if (connect_mysqldatabase("host","user","password","dbname",$mysqli))

        echo "ok";

}