Question

I have an ASP.NET site and I’ve been doing some work refactoring code to try to remove some long running processes (in the order of an hour) from the actual http Request by creating a BackgroundWorker and sending the work off to that to process. This was running fine on cutdown tests but when I applied the logic to the real code I found problems accessing Session variables from the code running in the Background Worker. It seems that the HttpContext object that was passed has a null session and if I ask for HttpContext.Current I get null back.

I’m assuming that this is because they are in a different thread and that the session and HttpContext.Current are both reliant on being in the same thread. Is there any way I can get access to the Session from the background worker or am I stuck with finding all the variables I need from session and putting them in an usable data structure and then putting them back in session (if appropriate) afterwards? It obviously complicates the refactor massively if I need to do this so I’d rather not.

Thanks for any thoughts you might have. I’m open to other suggestions on how I might do this other than BackgroundWorker processes (which were suggested to me in another question).

Answer 1

I’m not sure of all of your requirements, but you may be able to get away with using the Application Cache instead of the Session if you’re not looking for the long process to be tied to an individual user’s request.

If so, I would try swapping out your use of Session to:

HttpRuntime.Cache.Set("CacheKeyName");
HttpRuntime.Cache.Get("CacheKeyName");