How to clear browser cache with php?

Solution 1:

header("Cache-Control: no-cache, must-revalidate");
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Content-Type: application/xml; charset=utf-8");

Solution 2:

You can delete the browser cache by setting these headers:

<?php
header("Expires: Tue, 01 Jan 2000 00:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");
?>

Solution 3:

With recent browser support of "Clear-Site-Data" headers, you can clear different types of data: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Clear-Site-Data

header('Clear-Site-Data: "cache", "cookies", "storage", "executionContexts"');

Solution 4:

It seams you need to versionate, so when some change happens browser will catch something new and user won't need to clear browser's cache.

You can do it by subfolders (example /css/v1/style.css) or by filename (example: css/style_v1.css) or even by setting different folders for your website, example:

www.mywebsite.com/site1

www.mywebsite.com/site2

www.mywebsite.com/site3

And use a .htaccess or even change httpd.conf to redirect to your current application.

If's about one image or page:

    <?$time = date("H:i:s");?>
    <img src="myfile.jpg?time=<?$time;?>">

You can use $time on parts when you don't wanna cache. So it will always pull a new image. Versionate it seams a better approach, otherwise it can overload your server. Remember, browser's cache it's not only good to user experience, but also for your server.