Is there a way to determine how a page is called? I want to allow pages to 
only be called from my web application...not by someone pasting a url into 
the navigation bar. In other words, a response.redirect to a page is OK. A 
hyperlink from the application is OK, but a page load request from the 
navigation bar of the browser is not ok. I was hoping there was a way to 
use an httprequest member of httpcontext.current.request in some fashion 
to determine this. 'urlreferrer' looked like a candidate for awhile but I 
have menus in the application that are hyperlinks that leave urlreferrer 
set to nothing.