Php mail() - 优先级类型

Question

想知道什么是 php mail() 优先级类型。我读了这个question我阅读了 php 手册，

<?php
    $headers = "MIME-Version: 1.0\n" ;
    $headers .= "Content-Type: text/html; charset=\"iso-8859-1\"\n";
    $headers .= "X-Priority: 1 (Higuest)\n";
    $headers .= "X-MSMail-Priority: High\n";
    $headers .= "Importance: High\n";
    $status   = mail($to, $subject, $message,$headers);
?> 

但它没有解释我们可以使用哪些类型。 X-Priority: 1 (Higuest) 和 X-MSMail-Priority: High 两个不同的词用于此。我发现了几种优先级。例如:低、中、高、紧急、紧急、紧急我们如何使用这些类型。

Answer 1

值:1 = 高，3 = 正常，5 = 低

您不需要输入这两行，使用 X-MSMail-Priority 或 X-Priority

Alternative to X-Priority, although X-Priority is preferred. "High" corresponds to X-Priority: 1, "Normal" is the same as X-Priority: 3, and "Low" is the same as "X-Priority: 5". Including both X-Priority and X-MSMailPriority in the same email header is OK, although it probably best they agree.

Example:

either

X-MSMail-Priority: High

or

X-Priority: 1

通过这个链接，你会更加了解邮件功能

http://www.velvetblues.com/web-development-blog/avoid-spam-filters-with-php-mail-emails/