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HomeBackend DevelopmentPHP TutorialPHP禁止页面缓存的代码_php技巧

核心代码:

复制代码 代码如下:

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT");
header("Cache-Control: no-cache, must-revalidate");
header("Pramga: no-cache");

这对于某些页面来说是很有用的,例如:验证码,因为每次生成的验证码必须不同,否则验证码就没有任何意义了,这就可以用上面的语句实现禁止缓存。
再比如:“ 每回贴一次就换一个美女图片”,必须禁止页面缓存,否则返回的是缓存中相同的图片。
最近看到百度联盟上的《联盟志》-“如何让网民爱上你的网站”(主要是讨论如何提高用户体验的)联想到一点:
以论坛为例,当用户登陆后显示的是登陆后的 页面例如“管理”、“修改资料”等,当用户退出论坛后,再次返回刚才的页面,
仍然有“管理”、“修改资料”等(因为返回的是 缓存页面),虽然这时候cookie已经清空,“管理”、“修改资料”等已经不起作用了,
但是用户仍然以为这是有效的页面,从而认为别人也可以“管 理”、“修改资料”等,以为网站是不安全的(虽然实际上是安全的)。这时候在需要cookie验证的页面上加上上面的代码就有很用了,至少可以消除对于用户心 理的不良影响。
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