doppio controllo form

[DjBart]

Ciao
Prova cosi

<?php
//elabora_form.php


function ControlloEmail($email) {

    if (function_exists('filter_var')) {

        return filter_var($email, FILTER_VALIDATE_EMAIL) !== FALSE;

    } else {

        return preg_match('/^(?:[\w\!\#\$\%\&\'\*\+\-\/\=\?\^\`\{\|\}\~]+\.)*[\w\!\#\$\%\&\'\*\+\-\/\=\?\^\`\{\|\}\~]+@(?:(?:(?:[a-zA-Z0-9_](?:[a-zA-Z0-9_\-](?!\.)){0,61}[a-zA-Z0-9_-]?\.)+[a-zA-Z0-9_](?:[a-zA-Z0-9_\-](?!$)){0,61}[a-zA-Z0-9_]?)|(?:\[(?:(?:[01]?\d{1,2}|2[0-4]\d|25[0-5])\.){3}(?:[01]?\d{1,2}|2[0-4]\d|25[0-5])\]))$/', $email);

    }

}

$email = $_POST['email'];
$testo = $_POST['banner'];

if($email== null ){
echo"inserire un email";
}elseif($testo==null){
echo"inserire un testo";
}elseif(!ControlloEmail($email)){
echo"inserire un email valida";
}else{
mail('TuaEmail', 'Soggetto', $testo);
}

?>