PHP Code: 
<?php
class smtp

    {
    const NL = "\r\n";
    const READY = '220';
    const OK = '250';
    const TEXT64 = '334';
    const AUTHOK = '235';
    const DATAOK = '354';
    const BYE = '221';
    const MAILER = 'PHP smtp class';
    protected $_smtp = null;
    protected $_server = array(
        'host' => null,
        'port' => 25,
        'timeout' => 3,
    );
    protected $_user;
    protected $_pass;
    protected $_charset = 'UTF-8';
    protected $_from;
    protected $_mailFrom = null;
    protected $_replyTo = array();
    protected $_to = array();
    protected $_cc = array();
    protected $_bcc = array();
    protected $_priority;
    protected $_headers = array();
    protected $_subject;
    protected $_text = array(
        'body' => '',
        'Content-Type' => 'text/plain',
        'charset' => 'UTF-8'
    );
    protected $_attachments = array();
    protected $_raw = array();
    protected $_log = '';
    protected
    function _encode($W)
        {
        if ($this->_charset)
            {
            return '=?' . $this->_charset . '?B?' . base64_encode($W) . '?=';
            }
          else
            {
            return $W;
            }
        }

    protected
    function _recipients($N, $O, $K)
        {
        if (in_array($K, array(
            '_to',
            '_cc',
            '_bcc'
        )))
            {
            if ($O)
                {
                if ($N) $this->
                    {
                    $K}[$O] = $N;
                      else
                        {
                        if (isset($this->
                            {
                            $K}[$O])) unset($this->
                                {
                                $K}[$O]);
                                }
                            }
                          else
                            {
                            if ($N) $this->
                                {
                                $K}[] = $N;
                                }
                            }
                          else throw new Exception('Wrong recipient');
                        }

                    protected
                    function _dialog($Q, $d)
                        {
                        $this->_log.= $Q . PHP_EOL;
                        fwrite($this->_smtp, $Q . self::NL);
                        $F = fgets($this->_smtp);
                        $this->_log.= $F . PHP_EOL;
                        if (substr($F, 0, 3) != $d) throw new Exception('Message "' . $Q . '" NOT accepted! Here is the dialog dump:' . PHP_EOL . $this->_log);
                        return $F;
                        }

                    function _connect()
                        {
                        if (empty($this->_smtp))
                            {
                            if ($this->_smtp = fsockopen($this->_server['host'], $this->_server['port'], $e, $a, $this->_server['timeout']))
                                {
                                if (substr($F = fgets($this->_smtp) , 0, 3) != self::READY) throw new Exception('Server NOT ready! The server responded with this message:' . PHP_EOL . $F);
                                $this->_log = $F . PHP_EOL;
                                $f = explode('@', $this->_from['address']);
                                $this->_dialog('HELO ' . $f[1], self::OK);
                                if ($this->_user && $this->_pass)
                                    {
                                    $this->_dialog('auth login', self::TEXT64);
                                    $this->_dialog($this->_user, self::TEXT64);
                                    $this->_dialog($this->_pass, self::AUTHOK);
                                    }
                                }
                              else
                                {
                                $A = 'Unable to connect to ' . $this->_server['host'] . ' on port ' . $this->_server['port'] . ' within ' . $this->_server['timeout'] . ' seconds' . PHP_EOL;
                                if (!empty($a)) $A.= 'The remote server responded:' . PHP_EOL . $a . '(' . $e . ')';
                                throw new Exception($A);
                                }
                            }
                        }

                    function __construct($X, $Y = 25, $b = 3)
                        {
                        if (empty($X)) throw new Exception('Undefined SMTP server');
                        $this->_server['host'] = (string)$X;
                        if ($Y) $this->_server['port'] = (integer)$Y;
                        if ($b) $this->_server['timeout'] = (integer)$b;
                        }

                    function __destruct()
                        {
                        $this->_dialog('QUIT', self::BYE);
                        if ($this->_smtp) fclose($this->_smtp);
                        }

                    function auth($n, $g)
                        {
                        $this->_user = base64_encode($n);
                        $this->_pass = base64_encode($g);
                        }

                    function charset($E)
                        {
                        $this->_charset = (string)$E;
                        }

                    function from($J = null, $B = '')
                        {
                        if (null !== $J)
                            {
                            $this->_from['address'] = (string)$J;
                            $this->_from['name'] = (string)$B;
                            }

                        return $this->_from;
                        }

                    function mailFrom($V = null)
                        {
                        if (null !== $V) $this->_mailFrom = (string)$V;
                        return $this->_mailFrom;
                        }

                    function replyTo($Z = null, $B = null)
                        {
                        if (null !== $Z)
                            {
                            $this->_replyTo['address'] = (string)$Z;
                            $this->_replyTo['name'] = (string)$B;
                            }

                        return $this->_replyTo;
                        }

                    function to($m = null, $l = '')
                        {
                        $this->_recipients($m, $l, '_to');
                        return $this->_to;
                        }

                    function cc($i = null, $h = '')
                        {
                        $this->_recipients($i, $h, '_cc');
                        return $this->_cc;
                        }

                    function bcc($j = null, $k = '')
                        {
                        $this->_recipients($j, $k, '_bcc');
                        return $this->_bcc;
                        }

                    function priority($G = null)
                        {
                        if ($G)
                            {
                            $G = (integer)$G;
                            if (($G > 0) && ($G < 6)) $this->_priority = $G;
                              else throw new Exception('Priority are integer from 1 (low) to 5 (high)');
                            }

                        return $this->_priority;
                        }

                    function header($B = null, $P = null)
                        {
                        if ($B) $this->_headers[(string)$B] = (string)$P;
                        return $this->_headers;
                        }

                    function subject($U = null)
                        {
                        if (null !== $U) $this->_subject = (string)$U;
                        return $this->_subject;
                        }

                    function text($T = null, $I = 'text/plain', $E = 'utf-8')
                        {
                        if (null !== $T)
                            {
                            $this->_text = array(
                                'body' => str_replace("\n", self::NL, (string)$T) ,
                                'Content-Type' => $I,
                                'charset' => $E
                            );
                            }

                        return $this->_text;
                        }

                    function attachment($L = null, $B = '', $I = 'application/octet-stream', $E = 'utf-8')
                        {
                        if (is_readable($L))
                            {
                            $R = array(
                                'path' => (string)$L,
                                'Content-Type' => (string)$I,
                                'charset' => (string)$E
                            );
                            $B || ($B = pathinfo($L, PATHINFO_BASENAME));
                            $this->_attachments[$B] = $R;
                            }
                        elseif (!empty($L)) throw new Exception('File ' . $L . ' not found or not readable');
                        return $this->_attachments;
                        }

                    function raw($S = null, $B = '', $I = 'text/plain', $E = 'utf-8')
                        {
                        if ($S)
                            {
                            $R = array(
                                'content' => (string)$S,
                                'Content-Type' => (string)$I,
                                'charset' => (string)$E
                            );
                            if (empty($B)) $B = time() . '-' . mt_rand();
                            $this->_raw[$B] = $R;
                            }

                        return $this->_raw;
                        }

                    function clear()
                        {
                        $this->_to = array();
                        $this->_cc = array();
                        $this->_bcc = array();
                        $this->_headers = array();
                        $this->_attachments = array();
                        $this->_raw = array();
                        }

                    function send()
                        {
                        if (empty($this->_from)) throw new Exception('Sender undefined');
                        if (empty($this->_to) && empty($this->_cc) && empty($this->_bcc)) throw new Exception('No recipients');
                        if (empty($this->_subject)) throw new Exception('No subject');
                        if (empty($this->_text)) throw new Exception('No message text');
                        $this->_connect();
                        if ($this->_mailFrom) $J = $this->_mailFrom;
                          else $J = $this->_from['address'];
                        $this->_dialog('MAIL FROM:<' . $J . '>', self::OK);
                        foreach($this->_to as $C) $this->_dialog('RCPT TO:<' . $C . '>', self::OK);
                        foreach($this->_cc as $C) $this->_dialog('RCPT TO:<' . $C . '>', self::OK);
                        foreach($this->_bcc as $C) $this->_dialog('RCPT TO:<' . $C . '>', self::OK);
                        $this->_dialog('DATA', self::DATAOK);
                        $A = '';
                        if (empty($this->_from['name'])) $A.= 'From: <' . $this->_from['address'] . '>' . self::NL;
                          else $A.= 'From: "' . $this->_encode($this->_from['name']) . '"<' . $this->_from['address'] . '>' . self::NL;
                        if (!empty($this->_replyTo))
                            {
                            if (empty($this->_replyTo['name'])) $A.= 'Reply-To: <' . $this->_replyTo['address'] . '>' . self::NL;
                              else $A.= 'Reply-To: "' . $this->_encode($this->_replyTo['name']) . '"<' . $this->_replyTo['address'] . '>' . self::NL;
                            }

                        foreach($this->_to as $B => $C)
                            {
                            if (is_integer($B)) $A.= 'To: <' . $C . '>' . self::NL;
                              else $A.= 'To: "' . $this->_encode($B) . '"<' . $C . '>' . self::NL;
                            }

                        foreach($this->_cc as $B => $C)
                            {
                            if (is_integer($B)) $A.= 'Cc: <' . $C . '>' . self::NL;
                              else $A.= 'Cc: "' . $this->_encode($B) . '"<' . $C . '>' . self::NL;
                            }

                        foreach($this->_bcc as $B => $C)
                            {
                            if (is_integer($B)) $A.= 'Bcc: <' . $C . '>' . self::NL;
                              else $A.= 'Bcc: "' . $this->_encode($B) . '"<' . $C . '>' . self::NL;
                            }

                        if ($this->_priority) $A.= 'X-Priority: ' . $this->_priority . self::NL;
                        $A.= 'X-mailer: ' . self::MAILER . self::NL;
                        $A.= 'X-mailer-author: ' . self::MAILER_AUTHOR . self::NL;
                        foreach($this->_headers as $B => $P) $A.= $B . ': ' . $P . self::NL;
                        $A.= 'Date: ' . date('r') . self::NL;
                        $A.= 'Subject: ' . $this->_encode($this->_subject) . self::NL;
                        if ($this->_attachments || $this->_raw)
                            {
                            $M = hash('sha256', time());
                            $A.= 'MIME-Version: 1.0' . self::NL;
                            $A.= 'Content-Type: multipart/mixed; boundary=' . $M . self::NL;
                            $A.= self::NL;
                            $A.= 'This is a message with multiple parts in MIME format.' . self::NL;
                            $A.= '--' . $M . self::NL;
                            $A.= 'Content-Type: ' . $this->_text['Content-Type'] . '; charset=' . $this->_text['charset'] . self::NL;
                            $A.= self::NL;
                            $A.= $this->_text['body'] . self::NL;
                            foreach($this->_attachments as $B => $D)
                                {
                                $A.= '--' . $M . self::NL;
                                $A.= 'Content-Disposition: attachment; filename=' . $B . '; modification-date="' . date('r', filemtime($D['path'])) . '"' . self::NL;
                                if (substr($D['Content-Type'], 0, 5) == 'text/')
                                    {
                                    $A.= 'Content-Type: ' . $D['Content-Type'] . '; charset=' . $D['charset'] . self::NL;
                                    $A.= self::NL;
                                    $A.= file_get_contents($D['path']) . self::NL;
                                    }
                                  else
                                    {
                                    $A.= 'Content-Type: ' . $D['Content-Type'] . self::NL;
                                    $A.= 'Content-Transfer-Encoding: base64' . self::NL;
                                    $A.= self::NL;
                                    $A.= base64_encode(file_get_contents($D['path'])) . self::NL;
                                    }
                                }

                            foreach($this->_raw as $B => $H)
                                {
                                $A.= '--' . $M . self::NL;
                                $A.= 'Content-Disposition: attachment; filename=' . $B . '; modification-date="' . date('r') . '"' . self::NL;
                                if (substr($H['Content-Type'], 0, 5) == 'text/')
                                    {
                                    $A.= 'Content-Type: ' . $H['Content-Type'] . '; charset=' . $H['charset'] . self::NL;
                                    $A.= self::NL;
                                    $A.= $H['content'] . self::NL;
                                    }
                                  else
                                    {
                                    $A.= 'Content-Type: ' . $H['Content-Type'] . self::NL;
                                    $A.= 'Content-Transfer-Encoding: base64' . self::NL;
                                    $A.= self::NL;
                                    $A.= base64_encode($H['content']) . self::NL;
                                    }
                                }

                            $A.= '--' . $M . '--' . self::NL;
                            }
                          else
                            {
                            $A.= 'Content-Type: ' . $this->_text['Content-Type'] . '; charset=' . $this->_text['charset'] . self::NL;
                            $A.= self::NL . $this->_text['body'] . self::NL;
                            }

                        $A.= '.';
                        $c = $this->_dialog($A, self::OK);
                        return substr($c, 4);
                        }

                    function dump()
                        {
                        return $this->_log;
                        }
                    }
Basic usage



$smtp = new Smtp('smtp_server');
$smtp->from('user@domain');
$smtp->to('dest@anotherdomain');
$smtp->subject('subject');
$smtp->text('message');
$smtp->send();


Advanced usage



$smtp = new Smtp('smtp_server', 25, 3);
$smtp->from('user@domain', 'My name');
$smtp->mailFrom('my_account@domain');
$smtp->replyTo('anotheraddress@anotherdomain');
$smtp->priority(4);
$smtp->header('MyCustomHeader', 'The value of my custom header');
$smtp->to('addr1@domain', 'My friend');
$smtp->to('addr2@anotherdomain', 'Another friend');
$smtp->cc('addr3@domain', 'My mama');
$smtp->cc('addr4@domain', 'My papa');
$smtp->bcc('addr5@domain', 'My cat');
$smtp->subject('Birthday invitation');
$smtp->text('Want you come to my party?', 'text/plain', 'utf-8');
$smtp->attachment('/path/to/my/picture', 'me.jpg', 'image/jpeg');
$smtp->attachment('/path/to/businesscard', 'me.html', 'text/html', 'utf-8');
$smtp->raw('Here are directions to my home', 'directions.txt', 'text/plain', 'iso-8859-1');
$imagedata = imagecreatefrompng($imagefile);
// Add watermarks
ob_start();
imagepng($imagedata);
$stringdata = ob_get_contents(); // read from buffer
ob_end_clean();
$smtp->raw($stringdata, 'Flyer.jpg', 'image/jpeg');
$smtp->charset('UTF-8'); // For subject, names, etc.
$smtp->send();

$smtp->clear(); // Clear recipients and attachments
$smtp->from('anewsender@anewdomain');
$smtp->mailFrom('setanewmailfrom@anewdomain');
$smtp->replyTo('');
$smtp->to('anewdest@anothernewdomain');
$smtp->subject('newsubject');
$smtp->text('newmessage');
$smtp->send();

echo $smtp->dump(); // Dump the full logging


FEATURES


  • multiple recipients
  • To, Cc, Bcc recipients
  • named recipients
  • separate 'MAIL FROM' management
  • Reply-To management
  • priority management
  • custom headers
  • Content-Type equipped text (e.g. text/html)
  • attachments from file
  • attachments from string
  • binary attachments (from file or string)
  • Content-Type full management, per part
  • multiple dispatches in one connection
Kepler Reviewed by Kepler on . PHP SMTP Client <?php class smtp { const NL = "\r\n"; const READY = '220'; const OK = '250'; const TEXT64 = '334'; const AUTHOK = '235'; const DATAOK = '354'; Rating: 5