How to: Custom Prevent Caching?

After symcbean's answer I decided to change my question to:

What's the correct way to keep c开发者_如何学JAVAache of images/css/js only? Html will not be cached in any web browser.

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Go read some good books on the topic - or the specs. You're currently very badly informed.

A normal "trick" is to use:

Normal for whom? Setting Pragma: no-cache has nothing to do with what the browser caches. Setting Expires to -1 should prevent the current document from being cached - but its an HTTP/1.0 ONLY attribute - HTTP/1.1 has been in widespread use for the past 8 years.

However this is a very expensive decision. The cost is to retrieve all the images, css and javascript files in every request

No - the example you've given is an HTML tag - which can only occur in an HTML file. By default (i.e. in the absence of any specific caching directions) browsers "MAY" use cached file - in my experience, its only some mobile devices which cache so aggressively - but none of them implement the requirement to warn the user about this (see rfc 2616 13.1.5).

Caching instructions (and indeed all meta-data) should be sent in the HTTP headers - the META tags provide a surrogate mechanism in some cases.

Have a google for Mark Nottingham's caching tutorial - its a good starting point - but only a starting point.

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Configure your server to send the Pragma: no-cache and Expires: ... headers with html content. its trivial to do with apache in a .htaccess just add a files section with a pattern that matches any .html file and set the headers there using mod_headers or better yet mod_expires