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HTTP Expires header values “0” and “-1”3个
有谁能解释一下？
有谁能解释一下？
一般用于防止缓存.但是,本文档可能会为您提供更好的解释：
原文链接：https://www.f2er.com/php/131786.html报价：
Never use Expires = 0 to prevent caching. The Expires header is sent by the remote server and passed through to the browser by the Portal Server. Unless the time on all three machines is synchronized,an Expires=0 header can mistakenly return cached content. To solve this problem,set the Expires header to a fixed date that is definitely in the past.
