使用 SMTP 中继通过电子邮件发送附件答案

【问题标题】：Emailing attachments with SMTP Relay使用 SMTP 中继通过电子邮件发送附件
【发布时间】：2014-05-07 09:18:18
【问题描述】：

我目前有一台服务器将电子邮件中继到一个主邮件服务器，但是当我尝试发送带有附件的邮件时，它会出现：

Content-type:text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Email message
Content-Type: application/octet-stream; name="test.pdf"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="test.pdf"

有没有办法解决这个问题？

【问题讨论】：

标签： php email smtp

【解决方案1】：

试试这个

<?php
//define the receiver of the email
$to = 'youraddress@example.com';
//define the subject of the email
$subject = 'Test email with attachment';
//create a boundary string. It must be unique
//so we use the MD5 algorithm to generate a random hash
$random_hash = md5(date('r', time()));
//define the headers we want passed. Note that they are separated with \r\n
$headers = "From: webmaster@example.com\r\nReply-To: webmaster@example.com";
//add boundary string and mime type specification
$headers .= "\r\nContent-Type: multipart/mixed; boundary=\"PHP-mixed-".$random_hash."\"";
//read the atachment file contents into a string,
//encode it with MIME base64,
//and split it into smaller chunks
$attachment = chunk_split(base64_encode(file_get_contents('attachment.zip')));
//define the body of the message.
ob_start(); //Turn on output buffering
?>
--PHP-mixed-<?php echo $random_hash; ?> 
Content-Type: multipart/alternative; boundary="PHP-alt-<?php echo $random_hash; ?>"

--PHP-alt-<?php echo $random_hash; ?> 
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit

Hello World!!!
This is simple text email message.

--PHP-alt-<?php echo $random_hash; ?> 
Content-Type: text/html; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit

<h2>Hello World!</h2>
<p>This is something with <b>HTML</b> formatting.</p>

--PHP-alt-<?php echo $random_hash; ?>--

--PHP-mixed-<?php echo $random_hash; ?> 
Content-Type: application/zip; name="attachment.zip" 
Content-Transfer-Encoding: base64 
Content-Disposition: attachment 

<?php echo $attachment; ?>
--PHP-mixed-<?php echo $random_hash; ?>--

<?php
//copy current buffer contents into $message variable and delete current output buffer
$message = ob_get_clean();
//send the email
$mail_sent = @mail( $to, $subject, $message, $headers );
//if the message is sent successfully print "Mail sent". Otherwise print "Mail failed"
echo $mail_sent ? "Mail sent" : "Mail failed";
?>

【讨论】：

【解决方案2】：

正如 lemirage 所建议的，在 PHP 中滚动您自己的 MIME 编码将起作用。但是使用phpmailer可能更简单。 phpmailer 易于使用，用于发送带有附件的消息，并且设置简单——只需将几个 PHP 文件复制到您的服务器。见https://github.com/PHPMailer/PHPMailer

【讨论】：