Ciao a tutti...

avrei un form html fatto così

codice HTML:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Feedback Form</title>	
</head>
<body>
<h1>Send Us Your Feedback!</h1>
<form action="send_mail.php" method="post">
<table>
<tr>
<td>Email Adress:</td>
<td>
<input type="text" name="email_address" value="scrivi" maxlength="100" />
</td>
</tr><tr>
<td>Prova:</td>
<td>
<textarea rows="10" cols="50" name="prova"></textarea>
</td>
</tr><tr>
<tr>
<td>aaa:</td>
<td>

<label>Margherita</label><input type="checkbox" name="Margherita" value="checkboxValue" />
</td>
</tr>
<tr>
<tr>
<tr>
<td>Comments:</td>
<td>
<textarea rows="10" cols="50" name="comments"></textarea>
</td>
</tr>
<tr><td>&nbsp;</td>
<td>
<input type="submit" value="Submit" />
</td>
</tr>
</table>
</form>
</body>
</html>
e questo il relativo php
Codice PHP:
<?php

$webmaster_email 
"miaemail@gmail.com";

/*
This bit sets the URLs of the supporting pages.
If you change the names of any of the pages, you will need to change the values here.
*/
$feedback_page "feedback_form.html";
$error_page "error_message.html";
$thankyou_page "thank_you.html";

/*
This next bit loads the form field data into variables.
If you add a form field, you will need to add it here.
*/
$email_address $_REQUEST['email_address'] ;
$comments $_REQUEST['comments'] ;
$prova $_REQUEST['prova'] ;
$margherita $_REQUEST['Margherita'] ;

/*
The following function checks for email injection.
Specifically, it checks for carriage returns - typically used by spammers to inject a CC list.
*/
function isInjected($str) {
    
$injections = array('(\n+)',
    
'(\r+)',
    
'(\t+)',
    
'(%0A+)',
    
'(%0D+)',
    
'(%08+)',
    
'(%09+)'
    
);
    
$inject join('|'$injections);
    
$inject "/$inject/i";
    if(
preg_match($inject,$str)) {
        return 
true;
    }
    else {
        return 
false;
    }
}

// If the user tries to access this script directly, redirect them to the feedback form,
if (!isset($_REQUEST['email_address'])) {
header"Location: $feedback_page);
}

// If the form fields are empty, redirect to the error page.
elseif (empty($email_address) || empty($comments)) {
header"Location: $error_page);
}

// If email injection is detected, redirect to the error page.
elseif ( isInjected($email_address) ) {
header"Location: $error_page);
}

// If we passed all previous tests, send the email then redirect to the thank you page.
else {
mail"$webmaster_email""Ordine Pizze",
  
$comments$prova$Margherita"From: $email_address);
header"Location: $thankyou_page);
}
?>

se non metto nel codice "Margherita"... invio correttamente il form....
io vorrei aggiungere molti check e delle liste a selezione multipla, sempre da inviare per mail....
qualcuno riesce a darmi una mano? grazie