A me questo codice funziona perfettamente:
Codice PHP:
<form method="post">
<input type="text" name="antispam" value="5" />
<input type="hidden" name="rand_1" value="3" />
<input type="hidden" name="rand_2" value="2" />
<input type="submit" name="submit" value="Test"/>
</form>
<pre>
<?php
if (isset($_POST['submit'])) {
$antispam = isset($_POST['antispam']) ? (int)$_POST['antispam'] : 0;
$_POST['rand_1'] = isset($_POST['rand_1']) ? (int)$_POST['rand_1'] : 0;
$_POST['rand_2'] = isset($_POST['rand_2']) ? (int)$_POST['rand_2'] : 0;
$codice = $_POST['rand_1'] + $_POST['rand_2'];
var_dump($codice);
var_dump($antispam);
var_dump($antispam == $codice);
var_dump($antispam === $codice);
}
?>
</pre>