我使用 PHPMailer 类。我写了一封这样的测试电子邮件:
$mail = new PHPMailer();
$mail->SMTPDebug = 2;
$mail->Username = "username";
$mail->Password = "aaa";
$mail->SetFrom('mail', 'name');
$mail->AddReplyTo("mail","name");
$mail->Subject = "PHPMailer Test Subject via smtp, basic with authentication";
$mail->MsgHTML('BODYYY OF MESSAGE');
$address = "address";
$mail->AddAddress($address, "name");
$mail->addCC("mail", "name");
$mail->AddAttachment("a.jpg"); // attachment
$mail->Send();
一切都很好,但它没有附加标题,我看到它仅在调用 DKIM_add 函数时附加的代码。如何在没有 DKIM_add 功能的情况下发送主题?