How can I send an email with attachments from a PHP form?

Question

How can I send an email with attachments from a PHP form?

Answer 1

The HTML

There are really just two requirements in your HTML for sending file attachments.

• Your form needs to have this attribute: enctype="multipart/form-data"
• You need at least one field like <input type="file" name="examplefile">. This allows the user to browse for a file to attach.

If you have both of these, the browser will upload any attached files along with the form submission.

Side note: These are saved as temporary files on the server. For this example, we'll take their data and email it, but if you move the temporary files to a permanent location, you've just created a file upload form.

The MIME Email Format

This tutorial is great for understanding how to build up a MIME email (which can contain HTML content, a plain text version, attachments, etc) in PHP. I used it as a starting point.

Basically, you do three things:

• Declare up front that this email will have multiple types of content in it
• Declare a string of text that you will use to separate the different sections
• Define each section and stick in the appropriate content. In the case of file attachments, you have to specify the type and encode them in ASCII.
  • Each section will have a content-type such as image/jpg or application/pdf. More info can be found here. (My example script pulls this information from each file using built-in PHP functions.)

The PHP

Once the form is submitted, any files uploaded by the browser (see the HTML section) will be available via the $_FILES variable, which contains 'An associative array of items uploaded to the current script via the HTTP POST method.'

The documentation on $_FILES is lousy, but after an upload, you can run print_r($_FILES) to see how it works. It will output something like this:

Array ( [examplefile] => Array ( [name] => your_filename.txt 
[type] => text/plain [tmp_name] => 
C:\path\to\tmp\file\something.tmp [error] => 0 [size] => 200 ) ) 

You can then get the data in the associated temp file by using file_get_contents($_FILES['examplefile']['tmp_name']).

Side note on file size limits

php.ini has some settings that limit attachment size. See this discussion for more info.

An Example PHP Function

I created the following function, which can be included on the page and used to gather up any file attachments submitted with a form. Feel free to use it and/or adapt it for your needs.

The total attachment limit is arbitrary, but large amounts may bog down the mail() script or be rejected by a sending or receiving email server. Do your own testing.

(Note: The mail() function in PHP depends on information in php.ini to know how to send your email.)

function sendWithAttachments($to, $subject, $htmlMessage){
  $maxTotalAttachments=2097152; //Maximum of 2 MB total attachments, in bytes
  $boundary_text = "anyRandomStringOfCharactersThatIsUnlikelyToAppearInEmail";
  $boundary = "--".$boundary_text."\r\n";
  $boundary_last = "--".$boundary_text."--\r\n";

  //Build up the list of attachments, 
  //getting a total size and adding boundaries as needed
  $emailAttachments = "";
  $totalAttachmentSize = 0;
  foreach ($_FILES as $file) {
    //In case some file inputs are left blank - ignore them
    if ($file['error'] == 0 && $file['size'] > 0){
      $fileContents = file_get_contents($file['tmp_name']);
      $totalAttachmentSize += $file['size']; //size in bytes
      $emailAttachments .= "Content-Type: " 
      .$file['type'] . "; name=\"" . basename($file['name']) . "\"\r\n"
      ."Content-Transfer-Encoding: base64\r\n"
      ."Content-disposition: attachment; filename=\"" 
      .basename($file['name']) . "\"\r\n"
      ."\r\n"
      //Convert the file's binary info into ASCII characters
      .chunk_split(base64_encode($fileContents))
      .$boundary;
    }
  }
  //Now all the attachment data is ready to insert into the email body.
  //If the file was too big for PHP, it may show as having 0 size
  if ($totalAttachmentSize == 0) {
    echo "Message not sent. Either no file was attached, or it was bigger than PHP is configured to accept.";
   }
  //Now make sure it doesn't exceed this function's specified limit:
  else if ($totalAttachmentSize>$maxTotalAttachments) {
    echo "Message not sent. Total attachments can't exceed " .  $maxTotalAttachments . " bytes.";
  }
  //Everything is OK - let's build up the email
  else {    
    $headers =  "From: [email protected]\r\n";
    $headers .=     "MIME-Version: 1.0\r\n"
    ."Content-Type: multipart/mixed; boundary=\"$boundary_text\"" . "\r\n";  
    $body .="If you can see this, your email client "
    ."doesn't accept MIME types!\r\n"
    .$boundary;

    //Insert the attachment information we built up above.
    //Each of those attachments ends in a regular boundary string    
    $body .= $emailAttachments;

    $body .= "Content-Type: text/html; charset=\"iso-8859-1\"\r\n"
    ."Content-Transfer-Encoding: 7bit\r\n\r\n"
    //Inert the HTML message body you passed into this function
    .$htmlMessage . "\r\n"
    //This section ends in a terminating boundary string - meaning
    //"that was the last section, we're done"
    .$boundary_last;

    if(mail($to, $subject, $body, $headers))
    {
      echo "<h2>Thanks!</h2>Form submitted to " . $to . "<br />";
    } else {
      echo 'Error - mail not sent.';
    }
  }    
}

If you want to see what's going on here, comment out the call to mail() and have it echo the output to your screen instead.

Answer 2

nice tutorial here

The code

<?php
//define the receiver of the email
$to = '[email protected]';
//define the subject of the email
$subject = 'Test email with attachment';
//create a boundary string. It must be unique
//so we use the MD5 algorithm to generate a random hash
$random_hash = md5(date('r', time()));
//define the headers we want passed. Note that they are separated with \r\n
$headers = "From: [email protected]\r\nReply-To: [email protected]";
//add boundary string and mime type specification
$headers .= "\r\nContent-Type: multipart/mixed; boundary=\"PHP-mixed-".$random_hash."\"";
//read the atachment file contents into a string,
//encode it with MIME base64,
//and split it into smaller chunks
$attachment = chunk_split(base64_encode(file_get_contents('attachment.zip')));
//define the body of the message.
ob_start(); //Turn on output buffering
?>
--PHP-mixed-<?php echo $random_hash; ?> 
Content-Type: multipart/alternative; boundary="PHP-alt-<?php echo $random_hash; ?>"

--PHP-alt-<?php echo $random_hash; ?> 
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit

Hello World!!!
This is simple text email message.

--PHP-alt-<?php echo $random_hash; ?> 
Content-Type: text/html; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit

<h2>Hello World!</h2>
<p>This is something with <b>HTML</b> formatting.</p>

--PHP-alt-<?php echo $random_hash; ?>--

--PHP-mixed-<?php echo $random_hash; ?> 
Content-Type: application/zip; name="attachment.zip" 
Content-Transfer-Encoding: base64 
Content-Disposition: attachment 

<?php echo $attachment; ?>
--PHP-mixed-<?php echo $random_hash; ?>--

<?php
//copy current buffer contents into $message variable and delete current output buffer
$message = ob_get_clean();
//send the email
$mail_sent = @mail( $to, $subject, $message, $headers );
//if the message is sent successfully print "Mail sent". Otherwise print "Mail failed"
echo $mail_sent ? "Mail sent" : "Mail failed";
?>

Answer 3

For sending out the actual e-mail I would recommend using the PHPMailer library, it makes everything much easier.

Answer 4

You might want to check out SwiftMailer. It has a nice tutorial on this.