php表单文件上传noname文件

嗨，我有一段代码：

    <?php
$name = $_POST['name']; 
$email = $_POST['email'];
$phone = $_POST['phone'];
$company = $_POST['company'];
$phone = $_POST['phone'];
$address = $_POST['address'];
$address2 = $_POST['address1'];
$zip = $_POST['zip'];
$delivery = $_POST['delivery'];
$represents = $_POST['represent'];
$npairs = $_POST['npairs'];
$cuff = $_POST['cuff'];
$notes = $_POST['Text'];
    // Headers
        $headers = "From: $email";
        // create a boundary string. It must be unique
          $semi_rand = md5(time());
          $mime_boundary = "==Multipart_Boundary_x{$semi_rand}x";
          // Add the headers for a file attachment
          $headers .= "'nMIME-Version: 1.0'n" .
                      "Content-Type: multipart/mixed;'n" .
                      " boundary='"{$mime_boundary}'"";

        $fileatt      = $_FILES['artwork1']['tmp_name'];
        $fileatt_type = $_FILES['artwork1']['type'];
        $fileatt_name = $_FILES['artwork1']['name'];

$todayis = date("l, F j, Y, g:i a") ;
$attn = $attn ; 
$subject = $attn; 
$notes = stripcslashes($notes);
$interested = stripcslashes($interested);
$message = " $todayis [EST] 'n
From: $name 'n
e-mail: $email 'n
Phone: $phone 'n
Company: $company 'n
Phone: $phone'n
Address: $Address'n
State / Providence:  $address2'n 
Zip code: $zip
Country: $delivery
Represents: $represents
Number of pairs: $npairs
Style of Socks: $cuff

Message: $notes 'n 
";
        if (is_uploaded_file($fileatt)) {
          // Read the file to be attached ('rb' = read binary)
          $file = fopen($fileatt,'rb');
          $data = fread($file,filesize($fileatt));
          fclose($file);
          // Base64 encode the file data
          $data = chunk_split(base64_encode($data));
          // Add file attachment to the message
          $message .= "--{$mime_boundary}'n" .
                      "Content-Type: {$fileatt_type};'n" .
                      " name='"{$fileatt_name}'"'n" .
                      //"Content-Disposition: attachment;'n" .
                      //" filename='"{$fileatt_name}'"'n" .
                      "Content-Transfer-Encoding: base64'n'n" .
                      $data . "'n'n" .
                      "--{$mime_boundary}--'n";
        }


 );
mail("my@mail.com", 'My tittle', $message,$headers);
?>

但由于某种原因，当我在邮件中收到附件时，它没有任何信息，我收到了"noname"。没有扩展名或任何东西。。有人知道我哪里做错了吗？