Now that we know what tools PHP provides, let's write a quick application that will help us send messages with attachments. In order to send a message with an attachment, you need to send a mail header instructing that the email be sent as an attachment. A header might look like this:

Content-disposition: attachment; filename=myfile.doc

The header instructs the email to send the message as an attachment with a file called myfile.doc. So if you want to send a short message with an attachment, this is how it could look:

<?php

$to = " esme@holidays.com ";

$subject= "Lunch?";

$message = "This is my first test of the mail() function.";

$headers = "Content-disposition: attachment;

filename=myfile.docn";

$headers .= "cc:salles@mycompany.comn";

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

?>

Another very important step that you need to take when sending attachments is to set the content type for the file. The following are the available content types:

• image/gif
  
• image/jpeg
  
• audio/x-wav
  
• audio/vnd.rn-realaudio
  
• video/mpeg
  
• video/avi

You also may want to send application files. Some are text files, and some are binary files. For example, an RTF file is a text file, whereas a Word document is a binary file. Generally binary files are of type applica/octed stream. Binary files require encoding when they are sent through an email. PHP provides us with a function called chunk_split(), that does just that:

$encode = chunk_split(base64_encode($string));

In addition, when sending an encoded file, you need to inform the mail software that you intend to sent a encoded file. This is done in the headers section of the mail function:

Content-Transfer-Encoding: base64