As I said in the beginning, I started this series of articles by explaining how to build a basic MIME mailer class with PHP 4. This was only capable of sending messages in plain text. So let me quickly remind you of the definition of this introductory class. It looked like this:

class Mailer{

var $sender;

var $recipient;

var $subject;

var $headers=array();

function Mailer($sender,$recipient,$subject,$message){

// validate incoming parameters

if(!preg_match("/^.+@.+$/",$sender)){

trigger_error('Invalid value for email sender.',E_USER_ERROR);

}

if(!preg_match("/^.+@.+$/",$recipient)){

trigger_error('Invalid value for email recipient.',E_USER_ERROR);

}

if(!$subject||strlen($subject)>255){

trigger_error('Invalid length for email subject.',E_USER_ERROR);

}

if(!$message){

trigger_error('Invalid value for email message.',E_USER_ERROR);

}

$this->sender=$sender;

$this->recipient=$recipient;

$this->subject=$subject;

$this->message=$message;

// define some default MIME headers

$this->headers['MIME-Version']='1.0';

$this->headers['Content-Type']='multipart/mixed;boundary="MIME_BOUNDRY"';

$this->headers['From']='<'.$this->sender.'>';

$this->headers['Return-Path']='<'.$this->sender.'>';

$this->headers['Reply-To']=$this->sender;

$this->headers['X-Mailer']='PHP 4/5';

$this->headers['X-Sender']=$this->sender;

$this->headers['X-Priority']='3';

}

// create text part of the message

function buildTextPart(){

return "--MIME_BOUNDRY\nContent-Type: text/plain; charset=iso-8859-1\nContent-Transfer-Encoding: quoted-printable\n\n\n".$this->message."\n\n";

}

// create message MIME headers

function buildHeaders(){

foreach($this->headers as $name=>$value){

$headers[]=$name.': '.$value;

}

return implode("\n",$headers)."\nThis is a multi-part message in MIME format.\n";

}

// add new MIME header

function addHeader($name,$value){

$this->headers[$name]=$value;

}

// send email

function send(){

$to=$this->recipient;

$subject=$this->subject;

$headers=$this->buildHeaders();

$message=$this->buildTextPart()."--MIME_BOUNDRY--\n";

if(!mail($to,$subject,$message,$headers)){

trigger_error('Error sending email.',E_USER_ERROR);

}

return true;

}

}

As shown above, the previous “Mailer” class comes in handy for sending MIME-complaint messages in just plain text format, meaning that its functionality may be limited in certain situations. Despite this issue, below coded a short, hands-on example that shows how to use it in a simple way:

// create a new instance of the 'Mailer' class

$mailer=&new Mailer('alejandro@mydomain.com,'mybuddy@yourdomain.com','Testing mailer class','Hello buddy. Is everything doing fine over there?');

// send MIME email message

if($mailer->send()){

echo 'Message was sent successfully.';

}

That wasn’t rocket science. I have to admit that the mailer class in its current incarnation is pretty useless, particularly when used with PHP applications that require you to work with attachments. What comes next, though? Well, in accordance with the concepts that I deployed in the introduction, in the section to come I’m going to add a couple of additional methods to the pertaining “Mailer” class, so it can handle several types of attachments with relative ease.

To see how this will be done, please jump forward and read the next few lines. It’s only one click way.