We run our external website on Sharepoint 2007, and all the content is pulled from list data and generated using C# web parts.
Here is my problem: I have a web part on the home page that displays a random header banner on every page load. Unfortunately, Sharepoint seems to be caching this header and showing the same image every time, rather than randomizing it. I know this because the web part works properly for logged in users, and we've told SP to disable output caching for logged in users.
I would like to keep output caching enabled for anonymous users, but somehow tell sharepoint not to cache this particular web part. I know there's a way to do this, but it seems like there are so many different ways to approach caching and I don't know which one will work. I should note, I've tried using the PartCacheInvalidate method within the web part code, with no luck. Any ideas?
