如何使用Gmail API发送回复邮件

我正在使用Gmail API发送一封电子邮件，发送成功。我想知道如何用php回复那个已经发送的人。

在此附上我的发送代码：

$line = "
";
$strMailContent = $message;
$strMailTextVersion = strip_tags($strMailContent, '');

$strRawMessage = "";
$boundary = uniqid(rand(), true);
$subjectCharset = $charset = 'utf-8';

$strToMail = $to;

$strSubject = $subject;

$strRawMessage .= 'To: ' . ($strToMail)  . "
";

if(!empty($_POST['cc']) || !empty($_POST['bcc'])){
    $cc = $_POST['cc'];
    $bcc = $_POST['bcc'];
    $strRawMessage .= "Cc: $cc". $line;
    $strRawMessage .= "Bcc: $bcc". $line;
}

$strRawMessage .= 'Subject: =?' . $subjectCharset . '?B?' . base64_encode($strSubject) . "?=
";
$strRawMessage .= 'MIME-Version: 1.0' . "
";
$strRawMessage .= 'Content-type: Multipart/Mixed; boundary="' . $boundary . '"' . "
";



$filePath = $file_tmp_name;
$mimeType =  'text/plain; charset="UTF-8" ';
$fileName = $file_name;
$fileData = base64_encode(file_get_contents($filePath));

$strRawMessage .= "
--{$boundary}
";
$strRawMessage .= 'Content-Type: '. $mimeType .'; name="'. $fileName .'";' . "
";            
$strRawMessage .= 'Content-Description: ' . $fileName . ';' . "
";
$strRawMessage .= 'Content-Disposition: attachment; filename="' . $fileName . '"; size=' . filesize($filePath). ';' . "
";
$strRawMessage .= 'Content-Transfer-Encoding: base64' . "

";
$strRawMessage .= chunk_split(base64_encode(file_get_contents($filePath)), 76, "
") . "
";
$strRawMessage .= '--' . $boundary . "
";



$strRawMessage .= $strMailContent;

$mime = rtrim(strtr(base64_encode($strRawMessage), '+/', '-_'), '=');

$base64 = base64_encode($mime);
$data = '{ "raw" : "'.$mime.'" }';
$send = Qassim_HTTP(1, $url, $header, $data);

在这里，我将收件人地址作为已发送人员邮件ID传递，并且主题已是已使用的主题。

如何更改此代码以发送回复。请帮帮我

---

解决方案

您需要传递要回复的邮件的线程ID，并为新邮件设置相同的主题。我更喜欢使用某个库来生成消息的原始字符串，而不是手动编写，以便将出错的可能性降至最低。以下是使用PHPMailer的示例。

$gmail = new Google_Service_Gmail($client);
$message = new Google_Service_Gmail_Message();
$optParam = array();
$referenceId = '';
$thread = $gmail->users_threads->get($userId, $threadId);
$optParam['threadId'] = $threadId;
$threadMessages = $thread->getMessages($optParam);
$messageId = $threadMessages[0]->getId();
$messageDetails = $this->getMessageDetails($messageId); //omitted for simplicity: returns prepared message data.
$messageDetails = $messageDetails['data'];
$subject = $messageDetails['headers']['Subject'];
$mail = new PHPMailer();
$mail->CharSet = 'UTF-8';
$mail->From = $from_email;
$mail->FromName = $from_name;
$mail->addAddress($to);
$mail->Subject = $subject;
$mail->Body = $body;
$mail->preSend();
$mime = $mail->getSentMIMEMessage();
$raw = $this->Base64UrlEncode($mime); //omitted for simplicity: Encodes the data in base 64 format for sending.
$message->setRaw($raw);
$message->setThreadId($threadId);
$response = $gmail->users_messages->send($userId, $message);

userId是登录用户的ID，而threadId是您要回复的邮件的主题ID。

我在使用Google的PHPSDK时遇到了很多困难，而且缺乏合适的示例，所以我编写了一个涵盖Gmail API大部分函数的PHP包装器。它涵盖了上面的解释，如果你深入研究它，你会发现上面的例子中省略的逻辑。您可以找到here。