我的 Pragma HTTP 响应标头应设置为什么？

Question

我将与缓存相关的标头设置为在八小时后过期，如下所示...

header('Cache-Control: max-age=28800');
header('Expires:' . gmdate('D, d M Y H:i:s T', strtotime('+8 hours')));

在这种情况下，我的 Pragma HTTP 响应标头应该设置为什么？

Answer 1

您不必设置 pragma，仅当您想要无缓存指令时才设置 pragma。请参阅此处以获取更多信息： http://www.w3 .org/Protocols/rfc2616/rfc2616-sec14.html#sec14.32

Answer 2

请参阅 PHP 文档以了解 session_cache_limiter。您将看到要发送的正确缓存标头：

public:

Expires: (sometime in the future, according session.cache_expire)
Cache-Control: public, max-age=(sometime in the future, according to session.cache_expire)
Last-Modified: (the timestamp of when the session was last saved)

private_no_expire:

Cache-Control: private, max-age=(session.cache_expire in the future), pre-check=(session.cache_expire in the future)
Last-Modified: (the timestamp of when the session was last saved)

private:

Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: private, max-age=(session.cache_expire in the future), pre-check=(session.cache_expire in the future)
Last-Modified: (the timestamp of when the session was last saved)

nocache:

Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache