The following lines of code can be put into a .aspx file to prevent the resource from being cached on clients or proxies:

<%
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.Cache.SetNoStore();
%>

To prevent caching, these lines of code change the header of the server’s HTTP response by setting the following values:

• Cache-Control: no-cache, no-store
• Expires: -1
• Pragma: no-cache

You can read more about other possible caching options that can be passed to SetCacheability() here.