<?php
/*

   By Andreas Diegues
   Por Andreas Diegues

*/

function randCode($codeTotalChars) {

    for($i = 0; $i < $codeTotalChars; $i++) {
        $type[1] = "A|B|C|D|E|F|G|H|I|J|K|L|M|N|O|P|Q|R|S|T|U|V|X|W|Y|Z";
        $type[2] = "0|1|2|3|4|5|6|7|8|9";

        $randType = rand(1, 2);
        $type = explode("|", $type[$randType]);
        $max = count($type);
        
        $randChar = rand(0, $max);
        $code .= $type[$randChar];
    }
    
    return $code;
}

echo randCode(30);
# echo randCode(8); >> A 8 chars code
# echo randCode(8); >> Um código de 8 caracteres
?>