ASP.NET MVC 2 RC Caching Problem

Question

Since upgrading from mvc 2 beta 2 to rc I'm having trouble with an ajax submission in Internet Explorer. Upon carrying out a jquery form post, the function returns a url to a controller action. This worked fine with the controller action picking up it was a ajaxrequest and then piping back a partial view to update the page. This still works fine in Firefox, however in Internet Explorer the final call to the controller action now comes from cache and returns therefore returns a full view rather than partial.

I've tried setting the outputcache to 0 with no success and I've also tried the nocache actionfilter as described here http://stackoverflow.com/questions/1160105/asp-net-mvc-disable-browser-cache with no luck. The only way I can stop IE from pulling from cache is to physically delete the cached version.

Anyone have any ideas (apologies if this isn't very clear, tricky one to explain!)?

Answer 1

For some reason, IE is really aggressive about caching AJAX GETs. So if you are fetching that via AJAX, the behavior is not surprising to me. Also not surprising is that using output cache attribute didn't fix the problem, because it is IE, rather than the server, which is doing the caching. What you need to do is to tell IE not to cache the request, by setting the appropriate headers in the HTTP. Here is how we do it:

    [CacheControl(HttpCacheability.NoCache), HttpGet]
    public JsonResult DoStuff()
    {
        //...
    }

public class CacheControlAttribute : ActionFilterAttribute
{
    public CacheControlAttribute(HttpCacheability cacheability)
    {
        this._cacheability = cacheability;
    }

    private HttpCacheability _cacheability;

    public override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        HttpCachePolicyBase cache = filterContext.HttpContext.Response.Cache;
        cache.SetCacheability(_cacheability);
    }
}