How to disable client caching?

Question

PHP

The service uses dynamic updating of CSS and HTML file from iframe.
- .htaccess doesn't help.
- of course, no tags in CSS help.
- random(?x=yyy) GET request too. The files are saved in the cache.

Is there any other way to disable caching of the HTML and especially the CSS of the .

I check the result in chrome ( chrome://cache ) and in mozilla ( about://cache ). The files are still saved.

Answer 1

Google towards pragma headers for http