I am currently developing a web-part that generates a mega-menu for SharePoint 2010. The issue I am having is that when the user generates the menu, I have the web-part generate an HTML file and store it in SharePoint's style directory. The problem I am facing is how do I force SharePoint to refresh it's page cache to read the updated HTML file? I have no idea how to do this and my Google searches haven't turned up anything useful.
I know that I can save the file directly to disk and have SharePoint's cache monitor any modifications to the file and automatically update itself. However the problem with this solution is that we have multiple WFEs so the WFE that actually has the file written to it is the only server showing the updated menu.
Since this solution didn't work for us, I thought writing the HTML file to the style directory would allow all WFE's to see it. But I am stuck at how to force the cache to refresh itself after the is file updated. I know this is possible because if I modify the style sheet in the same directory, that automatically updates the look of the page on refresh.
Any suggestions on how to accomplish this would be greatly appreciated.