一个用Php Class写的发信程序
这个类里显示了发送MIME的方法，也就是HTML格式信件和附件发送的问题。

/*
Mail: An object to encapsulate the sending of email. Allows user-specified
From: addresses, handles the encoding of attachments; conforms more or less to
MIME standards.. Uses sendmail to send the mail, mimencode to do the MIME
encoding, and zip to automatically zip attachments.

Contacting the author(s):
Brought to you by the team at Sequoia Softworks, http://www.sequoiasoft.com
Feel free to contact tony@sequoiasoft.com and tell us how you like it!
(Or to complain bitterly, report bugs, or suggest new features.)

Known shortcomings/bugs:
o guessMIMEType()only knows about a few MIME types. You can expand this as
you need.
o $mime_boundary in the Send() method should be randomly generated, but it
isn't likely to ever hurt anything in its current form

Example:
require("Mail.phtml");
$mymessage = new Mail();
$mymessage->from = "php3.script@www.somedomain.net";
$mymessage->to = "luckyuser@destination.org";
$mymessage->subject = "This is your lucky day";
$mymessage->headers["Reply-To"] = "webmaster@www.somedomain.net";
$mymessage->headers["X-Extra-Header"] = "Pointless Header v3.0";
$mymessage->body = "Doesn't it feel good to get mail?nEspecially with files
attached!n";
$mymessage->attachments[0] = "tarball.tar.gz";
$mymessage->attachments[1] = "images/smiling_countenance.gif";
$mymessage->attachments[2] = "/usr/share/reference/jargondict.html";
$mymessage->attachments[3] = "./core";
$mymessage->attachments[4] = "/etc/passwd"; //naughty naughty!!
$mymessage->ZipAttachments("your_files.zip"); //uncomment this to zip all
//the attachments into one big
//attachment.
$mymessage->Send();
*/
class Mail {
var $from; //The sender
var $to; //The recipient
var $subject; //The subject line
var $headers; //A hash of additional headers (headername => headervalue)
var $zipname; //The name of the file the attachments are zipped into
//($zipname == false if attachments are to be sent
//individually)
var $attachments; //An array of files to attach
var $body; //The body text of the message

//Mail constructor: initializes vars to default values. 'Nuff said.
function Mail() {
$this->from = "";
$this->to = "";
$this->subject = "";
$this->headers = array();
$this->zipname = false;
$this->attachments = array();
$this->body = "";
}

//Auxiliary method, used to guess a file's MIME type
//based on its extension. Doesn't know about too many
//extensions right now
function guessMIMEType($filename) {
//GUESS MIME TYPE
$filename = basename($filename);
if(strrchr($filename,".") == false) {
return("application/octet-stream");
}

$ext = strrchr($filename,".");
switch($ext) {
case ".gif":
return "image/gif";
break;
case ".gz":
return "application/x-gzip";
case ".htm":
case ".html":
return "text/html";
break;
case ".jpg":
return "image/jpeg";
break;
case ".tar":
return "application/x-tar";
break;
case ".txt":
return "text/plain";
break;
case ".zip":
return "application/zip";
break;
default:
return "application/octet-stream";
break;
}
}

//Cute little convenience method. Supply it with a filename to
//zip attachments to, or supply it with false if attachments are
//sent individually
function ZipAttachments($name) {
$this->zipname = $name;
}

//The workhorse method, does the actually sending of the mail.
//Doesn't check for errors so be careful!
function Send($sendmail = "sendmail") {
if($this->from == "")
$fp = popen($sendmail . " -i " . $this->to, "w");
else
$fp = popen($sendmail . " -i -f"" . $this->from . ""
" . $this->to, "w");

$mime_boundary = "-1747901728-1448367683-913849620=:4553";

if($fp == false)
return false;

//Write subject header
fwrite($fp,"Subject: " . $this->subject . "n");

//Write user-defined headers
reset($this->headers);
while(list($hdrname,$hdrval) = each($this->headers)) {
fwrite($fp,$hdrname . ": " . $hdrval . "n");
}

//If there are attachments, this needs to be a MIME message
if(count($this->attachments) > 0) {
//Write MIME headers
fwrite($fp,"MIME-Version: 1.0n");
fwrite($fp,"Content-Type: multipart/mixed; BOUNDARY=""
. $mime_boundary . ""n");
fwrite($fp,"n");
//Write dummy message body
fwrite($fp," This message is in MIME format. The
first part should be readable text,n");
fwrite($fp," while the remaining parts are likely
unreadable without MIME-aware tools.n");
fwrite($fp," Send mail to
mime@docserver.cac.washington.edu for more info.n");
fwrite($fp,"n");

//Write message text
fwrite($fp,"--" . "$mime_boundary" . "n");
fwrite($fp,"Content-Type: text/plain; charset=US-
ASCIIn");
fwrite($fp,"n");
fwrite($fp,$this->body);
fwrite($fp,"n");

//Handle attachments
if($this->zipname != false) { //IF we've been told to
//zip the attachments
fwrite($fp,"--" . $mime_boundary . "n");
fwrite($fp,"Content-Type: application/zip; name=
"". $this->zipname . ""n");
fwrite($fp,"Content-Transfer-Encoding: base64
n");
//fwrite($fp,"Content-ID: " . $content_ID . "n");
fwrite($fp,"Content-Description:n");
fwrite($fp,"n");
$cmdline = "zip - ";
while(list($key, $attachment_name) = each($this->attachments))
$cmdline .= "$attachment_name ";
$cmdline .= "| mimencode -b";
$pp = popen($cmdline,"r");
while(!feof($pp)) {
$data = fread($pp,4096);
fwrite($fp,$data);
}
pclose($pp);
}
else { //no need to zip the attachments, attach them
//separately
while(list($key, $attachment_name) = each($this->attachments)) {
fwrite($fp,"--" . $mime_boundary . "n");
fwrite($fp,"Content-Type: " . $this->guessMIMEType($attachment_name) . ";
name="". basename($attachment_name) . ""n");
fwrite($fp,"Content-Transfer-Encoding: base64n");
//fwrite($fp,"Content-ID: " .
//$content_ID . "n");
fwrite($fp,"Content-Description:n");
fwrite($fp,"n");
$pp = popen("mimencode -b $attachment_name","r");
while(!feof($pp)) {
$data = fread($pp,4096);
fwrite($fp,$data);
}
pclose($pp);
}
}

fwrite($fp,"--" . $mime_boundary . "--n");
}
//No need for a MIME message, so it's an RFC822 message
else {
fwrite($fp,"n");
fwrite($fp,$this->body);
}
pclose($fp);
}
}
?>