一个低调有内涵的E-mail验证类！

这个类可以用来检查电子邮件是否有效使用SMTP协议。

它可以连接到由地址的域名来验证的MX记录中定义的SMTP服务器。

类模拟消息的传递，以查看是否在给定的收件人地址被接受为有效。

example.php

<?php

include_once 'class.verifyEmail.php';

$email = 'verify@codepearl.com';

$vmail = new verifyEmail();

if ($vmail->check($email)) {

echo 'email <' . $email . '> exist!';

} elseif ($vmail->isValid($email)) {

echo 'email <' . $email . '> valid, but not exist!';

} else {

echo 'email <' . $email . '> not valid and not exist!';

}

?>

class.verifyEmail.php

<?php

/**

* Class to check up e-mail

* @author liuxudong

* @copyright Copyright (c) 2010, liuxudong

*/

class verifyEmail {

/**

* User name

* @var string

*/

private $_fromName;

/**

* Domain name

* @var string

*/

private $_fromDomain;

/**

* SMTP port number

* @var int

*/

private $_port;

/**

* The connection timeout, in seconds.

* @var int

*/

private $_maxConnectionTimeout;

/**

* The timeout on socket connection

* @var int

*/

private $_maxStreamTimeout;

public function __construct() {

$this->_fromName = 'noreply';

$this->_fromDomain = 'localhost';

$this->_port = 25;

$this->_maxConnectionTimeout = 30;

$this->_maxStreamTimeout = 5;

}

/**

* Set email address for SMTP request

* @param string $email Email address

*/

public function setEmailFrom($email) {

list($this->_fromName, $this->_fromDomain) = $this->_parseEmail($email);

}

/**

* Set connection timeout, in seconds.

* @param int $seconds

*/

public function setConnectionTimeout($seconds) {

$this->_maxConnectionTimeout = $seconds;

}

/**

* Set the timeout on socket connection

* @param int $seconds

*/

public function setStreamTimeout($seconds) {

$this->_maxStreamTimeout = $seconds;

}

/**

* Validate email address.

* @param string $email

* @return boolean True if valid.

*/

public function isValid($email) {

return (false !== filter_var($email, FILTER_VALIDATE_EMAIL));

}

/*** Get array of MX records for host. Sort by weight information.

* @param string $hostname The Internet host name.

* @return array Array of the MX records found.

*/

public function getMXrecords($hostname) {

$mxhosts = array();

$mxweights = array();

if (getmxrr($

hostname, $mxhosts, $mxweights)) {

array_multisort($mxweights, $mxhosts);

}

/**

* Add A-record as last chance (e.g. if no MX record is there).

* Thanks Nicht Lieb.

*/

$mxhosts[] = $hostname;

return $mxhosts;

}

/**

* check up e-mail

* @param string $email Email address

* @return boolean True if the valid email also exist

*/

public function check($email) {

$result = false;

if ($this->isValid($email)) {

list($user, $domain) = $this->_parseEmail($email);

$mxs = $this->getMXrecords($domain);

$fp = false;

$timeout = ceil($this->_maxConnectionTimeout / count($mxs));

foreach ($mxs as $host) {

// if ($fp = @fsockopen($host, $this->_port, $errno, $errstr, $timeout)) {

if ($fp = @stream_socket_client("tcp://" . $host . ":" . $this->_port, $errno, $errstr, $timeout)) {

stream_set_timeout($fp, $this->_maxStreamTimeout);

stream_set_blocking($fp, 1);

// stream_set_blocking($fp, 0);

$code = $this->_fsockGetResponseCode($fp);

if ($code == '220') {

break;

} else {

fclose($fp);

$fp = false;

}

}

}

if ($fp) {

$this->_fsockquery($fp, "HELO " . $this->_fromDomain);

//$this->_fsockquery($fp, "VRFY " . $email);

$this->_fsockquery($fp, "MAIL FROM: <" . $this->_fromName . '@' . $this->_fromDomain . ">");

$code = $this->_fsockquery($fp, "RCPT TO: <" . $user . '@' . $domain . ">");

$this->_fsockquery($fp, "RSET");

$this->_fsockquery($fp, "QUIT");

fclose($fp);

if ($code == '250') {

/**

* http://www.ietf.org/rfc/rfc0821.txt

* 250 Requested mail action okay, completed

* email address was accepted

*/

$result = true;

} elseif ($code == '450' || $code == '451' || $code == '452') {

/**

* http://www.ietf.org/rfc/rfc0821.txt

* 450 Requested action not taken: the remote mail server

* does not want to accept mail from your server for

* some reason (IP address, blacklisting, etc..)

* Thanks Nicht Lieb.

* 451 Requested action aborted: local error in processing

* 452 Requested action not taken: insufficient system storage

* email address was greylisted (or some temporary error occured on the MTA)

* i believe that e-mail exists

*/

$result = true;

}

}

}

return $result;

}

/**

* Parses input string to array(0=>user, 1=>domain)

* @param string $email

* @return array

* @access private

*/

private function _parseEmail(&$email) {

return sscanf($email, "%[^@]@%s");

}

/**

* writes the contents of string to the file stream pointed to by handle $fp

* @access private

* @param resource $fp

* @param string $string The string that is to be written

* @return string Returns a string of up to length - 1 bytes read from the file pointed to by handle.

* If an error occurs, returns FALSE.

*/

private function _fsockquery(&$fp, $query) {

stream_socket_sendto($fp, $query . "/r/n");

return $this->_fsockGetResponseCode($fp);

}

/**

* Reads all the line long the answer and analyze it.

* @access private

* @param resource $fp

* @return string Response code

* If an error occurs, returns FALSE

*/

private function _fsockGetResponseCode(&$fp) {

$reply = stream_get_line($fp, 1);

$status = stream_get_meta_data($fp);

if ($status['unread_bytes']>0)

{

$reply .= stream_get_line($fp, $status['unread_bytes'],"/r/n");

}

preg_match('/^(?[0-9]{3})(/s|-)(.*)$/ims', $reply, $matches);

$code = isset($matches['code']) ? $matches['code'] : false;

return $code;

}

}

?>