How do I determine if a request is the result of a postback?
<p><strong>Update</strong></p>

<p>I'm implementing a custom page caching solution and I don't want the request to be cached or retrieved from the cache if it's in response to a form submission or some sort of asp.net postback.</p>

<p>I'm trying to figure out if the current HttpRequest is a postback. Is there a way of doing this outside the context of a page or other usercontrol? In otherwords if I'm inside an HttpModule I don't have access to <code>this.IsPostBack</code> but I still need to determine if it is in fact a postback.</p>

<p>Also, are postbacks always "Post" requests or is that determined by containing form?</p>

<p>thanks!</p>
