Question

How do I force IIS 7 to not cache images for a particular page?

Answer 1

In IIS7, you can do this either declaratively in your web.config, or programmatically.

<location path="YourPath">
  <system.webServer>
    <staticContent>
      <clientCache cacheControlMode="DisableCache" />
    </staticContent>
  </system.webServer>
</location>

The programmatic solution requires a simple HttpModule that’s registered to run for all requests in Integrated mode, where you look for the URLs that you’re concerned about. Then call:

context.Response.Cache.SetCacheability(HttpCacheability.NoCache);

FWIW, you may want to consider disabling client-side caching only, while enabling server-side caching, by using HttpCacheability.ServerAndNoCache. Also, if you add a query string on the image names, you will prevent server-side caching by http.sys.

In case it helps, I cover techniques like these in detail in my book: Ultra-Fast ASP.NET.