Random Key Generator

<?php

echo randomkeys(); //random 16 chars

echo randomkeys(7); //random 7 chars

function randomkeys($length=16){
        $pattern = "1234567890abcdefghijklmnopqrstuvwxyz"; //You can put any characters you want in here
        for($i=0;$i<$length;$i++)
        {
                $key .= $pattern{rand(0,strlen($pattern))};
        }
        return $key;
}

?>