Question

I have a scenario where the main website (which I have no control over) is loading my website from within an iframe. It’s a GET with query string parameters chosen by the user on the main website. The issue is that IE caches my first page inside of that iframe.

I applied the following meta tags:

<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"/>

But IE is still caching it just for about 15 – 20 seconds or so. So if the user quickly goes back to the main website and chooses something else, they would see the cached version of my first page. What can I do here?

Answer 1

Try busting the cache from the server by setting appropriate HTTP response headers:

public class NoCacheAttribute : ActionFilterAttribute
{  
    public override void OnResultExecuting(ResultExecutingContext filterContext)
    {
        var cache = filterContext.HttpContext.Response.Cache;
        cache.SetExpires(DateTime.UtcNow.AddDays(-1));
        cache.SetValidUntilExpires(false);
        cache.SetRevalidation(HttpCacheRevalidation.AllCaches);
        cache.SetCacheability(HttpCacheability.NoCache);
        cache.SetNoStore();
    }
}

and then decorate your controller action that is supposed to serve the <iframe> with this attribute:

[NoCache]
public ActionResult Foo()
{
    ...
}