强适应性的PHP邮件发送类（采用邮件专递方式，无需smtp服务器）

本类参考了网上关于PHP的MIME MAIL和SMTP发送协议的文章,本类可以在*NUX或WIN平台下并且无需SMTP服务器,直接通过邮件专递方式送到邮件接收方的邮件服务器中。

需要注意的是在发送大尺寸邮件时，建议在服务器允许MAIL()发送的情况下，尽量开启'usemail'=>true，因为用PHP的SOCKE方式发送效率相对于MAIL()函数来说要低；另外要说明的是由于采用邮件专递的方式邮件没有本地暂存发送，为了可靠性和避免长时间等待的过时问题，所以在没有启用PHP的MAIL函数时，本类没有添加支持用通过分号分隔的多帐号同时发送的功能。

本类在nease.net的Linux+php5虚拟主机空间(该空间不能使用PHP自带的MAIL函数发邮件，写此类当时就是为了在这个空间下发送邮件)及win2003+IIS6+php4.3上测试成功。

简单范例：

require("mailer.class.php");
$mailer=new mailer();
$mailer->mConfig['mailform']="xxx@21cn.com";
$isended=$mailer->mail("nobody@example.com","the subject","hello","From: webmaster@example.com");
if($isended)
{
echo "true";
}
else
{
echo "false";
}

类文件: mailer.class.php

<?php
/**
* Project: Dowebs.Lib: the PHP compiling template engine
* File: mailer.lib.php
*
* This library is opensource software;
* @link http://www.dowebs.net/ * @copyright 2004-2005 dowebs.net studio.
* @author Xie Hengduo xiejuchen@21cn.com
* @package System
* @version 1.0.0.0
*/
class mailer{
var $mConfig=array(
'dns' =>"202.96.104.16", //设置解域MX记录的域名服务器
'mailform' =>"yourname@yourdomain.com",//发送邮件的帐号
'charset' =>"utf-8", //HTML附件编码
'usemail' =>false //是否使用PHP中的MAIL函数
);
var $dns_repl_domain="";
var $arrMX =array();
var $error ="";

var $aattach =array();
var $xheaders =array();
var $ctencoding = "7bit";
var $priorities = array( '1 (Highest)', '2 (High)', '3 (Normal)', '4 (Low)', '5 (Lowest)' );
var $content_type='';

function mailer()
{

}

//兼容的mail函数
function mail($to,$subject,$message,$additional_headers='')
{
if($this->mConfig['usemail'])
{
return mail($to,$subject,$message,$additional_headers);
}
else
{
if($this->queryMailStmp($to))
{
$this->error="2 收件人邮箱地址非法";
return false;
}
//连接服务器
$is_sockopen=false;
$hostname="";
foreach($this->arrMX as $value)
{
if($fp = fsockopen ($value, 25, $errno, $errstr, 60))
{
$hostname=$value;
$is_sockopen=true;
break;
}
}
if (!$is_sockopen){$this->error="3 联接服务器失败";return false;}

//HELO
fputs($fp,"HELO {$hostname}/r/n");
$lastmessage = fgets($fp,1024);
if(substr($lastmessage,0,3) != 220 ){$this->error="4 错误信息$lastmessage";return false;}
//FROM:
fputs( $fp,"MAIL FROM:<{$this->mConfig['mailform']}>"."/r/n");
$lastmessage = fgets ($fp,1024);
if (substr($lastmessage,0,3) != 250){$this->error="5 错误信息$lastmessage";return false;}
//TO:
fputs( $fp,"RCPT TO:<$to>"."/r/n");
$lastmessage = fgets ($fp,1024);
if (substr($lastmessage,0,3) != 250){$this->error="6 错误信息$lastmessage";return false;}
while(true){
$lastmessage = fgets($fp,512);
if((substr($lastmessage,3,1) != "-")||(empty($lastmessage)))break;
}
//DATA
fputs($fp,"DATA/r/n");
$lastmessage = fgets ($fp,1024);
if (substr($lastmessage,0,3) != 354){$this->error="7 错误信息$lastmessage";return false;}
$message="/n".$message;
if($additional_headers!='')
{
$message = $additional_headers."/r/n".$message;
}
//处理To头
$head="To: $to/r/n";
$message = $head.$message;
//处理Subject头
$head="Subject: $subject/r/n";
$message = $head.$message;
//加上结束串
$message .= "/r/n./r/n";
//发送信息
fputs($fp, $message);
fputs($fp,"QUIT/r/n");
fclose($fp);
return true;
}
}

//邮址初步校验
function is_valid_email ($email = "")
{
return preg_match('/^[./w-]+@([/w-]+/.)+[a-zA-Z]{2,6}$/',$email);
}

function queryMailStmp($mailaddr)
{
if($this->is_valid_email($mailaddr))
{
$this->mxlookup(substr(strstr($mailaddr,'@'),1));
}
else
{
return false;
}
}
//取得MX记录
function mxlookup($domain)
{
if(function_exists('getmxrr'))
{
getmxrr($domain,$this->arrMX);
}
else
{
##########################
$dot_pos = 0; $temp = "";
$QNAME="";
while($dot_pos=strpos($domain,"."))
{
$temp = substr($domain,0,$dot_pos);
$domain = substr($domain,$dot_pos+1);
$QNAME .= chr(strlen($temp)).$temp;
}
$QNAME .= chr(strlen($domain)).$domain.chr(0);
###########################
$dns_packet = chr(0).chr(1).chr(1).chr(0).chr(0).chr(1).chr(0).chr(0).chr(0).chr(0).chr(0).chr(0).$QNAME.chr(0).chr(15).chr(0).chr(1);
$dns_socket = fsockopen("udp://{$this->mConfig['dns']}", 53);
fwrite($dns_socket,$dns_packet,strlen($dns_packet));
$this->dns_reply = fread($dns_socket,1);
$bytes = stream_get_meta_data($dns_socket);
$this->dns_reply .= fread($dns_socket,$bytes['unread_bytes']);
fclose($dns_socket);
$this->cIx=6;
$this->Total_Accounts="";
for($i=0;$i<2;$i++){
$this->Total_Accounts.=ord(substr($this->dns_reply,$this->cIx,1));
$this->cIx++;
}
$this->cIx+=4;
$this->parse_data($this->dns_repl_domain);
$this->cIx+=7;
for($ic=1;$ic<=$this->Total_Accounts;$ic++) {
$QTYPE = ord($this->gdi($this->cIx));
if($QTYPE!==15){
print("<font color='red' size='4' face='verdana'><B>[No MX Records returned]</b></font>");
die();
}
$this->cIx+=9;
$mxPref = ord($this->gdi($this->cIx));
$this->parse_data($curmx);
$this->arrMX[] =$curmx;
$this->cIx+=3;
}
}
}
function gdi(&$cIx,$bytes=1) {
$this->cIx++;
return(substr($this->dns_reply, $this->cIx-1, $bytes));
}
function parse_data(&$retval) {
$arName = array();
$byte = ord($this->gdi($this->cIx));
while($byte!==0) {
if($byte==192) { //compressed
$tmpIx = $this->cIx;
$this->cIx = ord($this->gdi($cIx));
$tmpName = $retval;
$this->parse_data($tmpName);
$retval = $retval.".".$tmpName;
$this->cIx = $tmpIx+1;
return;
}
$retval="";
$bCount = $byte;
for($b=0;$b<$bCount;$b++) {
$retval .= $this->gdi($this->cIx);
}
$arName[]=$retval;
$byte = ord($this->gdi($this->cIx));
}
$retval=join(".",$arName);
}

############################################
# MIME MAIL CODE
############################################
function From( $from="")
{
if($from=='')
{
$this->xheaders['From']=$this->mConfig['mailform'];
}
else
{
$this->xheaders['From'] = $from;
}
}

function mimemail($to,$subject,$message)
{
$this->boundary= "--" . md5( uniqid("myboundary") );
if( $this->mConfig['charset'] != "us-ascii" )
{
$this->ctencoding = "8bit";
}
$headers = "";
if( $this->mConfig['charset'] != "") {
//global $contenttype;
$this->xheaders["Mime-Version"] = "1.0";
$this->xheaders["Content-Type"] = "{$this->content_type}; charset={$this->mConfig['charset']}";
$this->xheaders["Content-Transfer-Encoding"] = $this->ctencoding;
}
$this->xheaders["X-Mailer"] = "Dowebs.net Mailer";
if( count( $this->aattach ) > 0 )
{
$this->xheaders["Content-Type"] = "multipart/mixed;/n boundary=/"{$this->boundary}/"";
$fullBody="This is a multi-part message in MIME format./n--{$this->boundary}/n";
$fullBody.= "Content-Type: text/html; charset={$this->mConfig['charset']}/nContent-Transfer-Encoding:{$this->ctencoding}/n/n".message."/n";
$sep= chr(13) . chr(10);
$ata= array();
$k=0;
for( $i=0; $i < count( $this->aattach); $i++ ) {
$filename = $this->aattach[$i];
$basename = basename($filename);
$ctype = $this->actype[$i]; // content-type
$disposition = $this->adispo[$i];
if(!file_exists( $filename)){$this->error="1 Class Mail, method attach : file {$filename} can't be found";return false;}
$subhdr= "--{$this->boundary}/nContent-Type: {$ctype};/n name=/"{$basename}/";/nContent-Transfer-Encoding: base64/nContent-Disposition: {$disposition};/n filename=/"{$basename}/"/n";
$ata[$k++] = $subhdr;
$linesz= filesize( $filename)+1;
$fp= fopen( $filename, 'r' );
$ata[$k++] = chunk_split(base64_encode(fread( $fp, $linesz)));
fclose($fp);
}
$fullBody .= implode($sep, $ata);
}
else
{
$fullBody = $message;
}
reset($this->xheaders);
while( list( $hdr,$value ) = each( $this->xheaders)) {
$headers .= "$hdr: $value/n";
}

return $this->mail($to,$subject,$fullBody,$headers);
}
function Attach($filename,$filetype = "",$disposition = "inline")
{
if( $filetype == "" )
{
$filetype = "application/x-unknown-content-type";
}
$this->aattach[] = $filename;
$this->actype[] = $filetype;
$this->adispo[] = $disposition;
}

function Content_type($contenttype)
{
$this->content_type=$contenttype;
}

function Priority($priority)
{
if(!intval($priority))return false;
if(!isset($this->priorities[$priority-1]))return false;
$this->xheaders["X-Priority"] = $this->priorities[$priority-1];
return true;
}

}
?>