Cookies help

[miligraf]

I have installed a rating system at my site but i want to limit every person to 1 vote per file. What i have tried (with cookies) is that when a person votes, it creates a new cookie with that file id and if the cookie was made, then compare if the id's to see if the person is trying to vote again for the same file.

 

I had some reading of cookies but still cant make it...this if what i got so far, maybe im just confused lol:

 

<?php
function votar(){
//do something and then:
$i=descarga;
$viejaid=$id;
$viejadescarga=$i++;
setcookie("$viejadescarga", $viejaid);
}
if (!isset($_COOKIE['$viejadescarga'])){
setcookie("descarga", $id);
votar();
} else {
foreach ($_COOKIE['$viejadescarga'] as $viejadescarga => $viejaid){
	if ($viejaid==$id) {
?>
//Just one vote per file!
<?php
} else {
votar();
}}}
foreach ($_COOKIE as $viejadescarga => $viejaid){
print_r($_COOKIE);
}
?>

 

If there is a better way to have this done let me know, thanks!!!