通过mail（）PHP传递文件

I have a Problem, I would like to send a File (Photoshop, .gif etc.) File via Email with PHP. I POST the Data from the HTML Document to the following PHP File. The Problem: I receive the Email but the File is corrupt. Any Idea why this doesn´t work??

    $to = 'admin@example.com'; 
    $subject = 'Order';

    $name = strip_tags($_POST['name']);
    $email = strip_tags($_POST['email']);
    $plz = strip_tags($_POST['plz']);
    $city = strip_tags($_POST['city']);
    $street = strip_tags($_POST['street']);
    $nr = strip_tags($_POST['nr']);

    $plzdelivery = strip_tags($_POST['plz-delivery']);
    $citydelivery = strip_tags($_POST['city-delivery']);
    $streetdelivery = strip_tags($_POST['street-delivery']);
    $nrdelivery = strip_tags($_POST['nr-delivery']);

    $buttonsize = strip_tags($_POST['button-size']);
    $count = strip_tags($_POST['count']);

    $message = "Name: ".$name." Email: ".$email." Plz: ".$plz." Stadt: ".$city." Strasse: ".$street." Hnr: ".$nr." Button: ".$buttonsize." Anzahl: ".$count;

    $type = $_FILES['file']['type'];
    $attachment = chunk_split(base64_encode(file_get_contents($_FILES['file']['tmp_name'])));
    $filename = $_FILES['file']['name'];

    $boundary =md5(date('r', time())); 

    $headers = "From: webmaster@example.com
Reply-To: webmaster@example.com";
    $headers .= "
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary=\"_1_$boundary\"";

    $message="This is a multi-part message in MIME format.
--_1_$boundary
Content-Type: multipart/alternative; boundary=\"_2_$boundary\"

--_2_$boundary
Content-Type: text/plain; charset=\"iso-8859-1\"
Content-Transfer-Encoding: 7bit

$message

--_2_$boundary--
--_1_$boundary
Content-Type: application/octet-stream; name=\"$filename\" 
Content-Transfer-Encoding: base64 
Content-Disposition: attachment 

$attachment
--_1_$boundary--";

    mail($to, $subject, $message, $headers);

Short answer: Don't even try.

PHP's mail() function is very very short on features. If you're even considering trying to send attachments using it, you are in for a lot of frustration and wasted time.

The best answer I can give you is to use a third party library. There are several good ones available. Why waste weeks of your time writing something that isn't going to be good enough when others have already spent years doing it for you and getting it right.

My suggestion would be phpMailer, but several others exist as well.

You should install the pear Mail_Mime package, it will allow you to easily attach a file.

http://pear.php.net/manual/en/package.mail.mail-mime.addattachment.php