Nakupny kosik

//produkty

$sql = MySQL_Query("SELECT * FROM produkty ORDER BY ID");
while ($r = MySQL_Fetch_Array($sql)) {
$cena = $r['cena'];
$id = $r['id'];

echo "<form action='index.php' method='POST'>";
echo "<input type='hidden' name='id' value='$id'>
echo "<input type='hidden' name='cena' value='$cena'>
echo "<input type='text' name='ks'>";
echo "<input type='submit' name='kupit' value='kupit'>";
echo "</form>";
}

//pridanie do kosika
if($_POST['kupit']) {
$id = $_POST['id'];
$cena = $_POST['cena'];
$ks = $_POST['ks'];

$tovar = array (
'id' => $id,
'cena' => $cena,
'ks' = $ks
);

//a teraz by som potreboval $tovar vlozit do $_SESSION['kosik'][] = $tovar;
//a potom nejako ten session vzpisat ako obsah kosika, viete ma niekto nakopnut ? neviem si rady. dakujem
}

$_SESSION['kosik'][] = $tovar;

<?php
        foreach ($_SESSION['kosik'] as $index => $hodnota) {
        echo "$index"<br />";
        }
        ?>