Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0
The PHP way would look like:
header('Cache-Control: no-cache, no-store, must-revalidate'); // HTTP 1.1.
header('Pragma: no-cache'); // HTTP 1.0.
header('Expires: 0'); // Proxies.
The Java/Servlet way would look like:
response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
response.setHeader("Pragma", "no-cache"); // HTTP 1.0.
response.setDateHeader("Expires", 0); // Proxies.
The ASP.NET way would look like:
Response.AppendHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
Response.AppendHeader("Pragma", "no-cache"); // HTTP 1.0.
Response.AppendHeader("Expires", "0"); // Proxies.
The plain HTML way would look lile:
<meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate">
<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Expires" content="0">
The Cache-Control is per the HTTP 1.1 spec for clients (and implicitly required by some browsers next to Expires),
the Pragma is per the HTTP 1.0 spec for clients and proxies and Expires is per the HTTP 1.1 spec for clients and proxies. Other Cache-Control parameters are irrelevant if the abovementioned three are specified. The Last-Modified header is only intersting if you actually want to cache the request.
