Alternative way of Page.IsPostBack

I am into iPhone, Android and Blackberry web programming. I am struck into an issue in which i either need to stop refresh of page (which according to blogs is not possible) or i need to just refresh the page rather than submitting.

I have used basic HTML controls not ASP.Net server controls, so Page.IsPostBack cannot be used to differentiate between page refresh and a postback.

Alternatives that i have tried:

The root of the issue is that : Having used Request.Form Collection which are read only and are only updated on a postback. So, on a page refresh the Request.Form collection is having previous values and thus submits according to previous request.

I have tried using cookies as found in this link: http://hi.baidu.com/cxyking/blog/item/508872346135283c5ab5f53c.html

It is able to detect a page refresh only after it has already loaded. While my requirement is that i need to detect page refresh before the original page has been unloaded.

I tried to use OnBeforeUnload to display some warning message. But, this only works in desktop browsers and iOS does not seem to do anything on this event.

Is there any idea on how i can do any one of following:

• Completely stop 开发者_StackOverflow社区page refresh.
• Display warning message to user for not leaving the page (OnBeforeUnload not working on iOS)
• Somehow, update Request.Form Collection (Note that it has a Set but it is readonly, so it doesnt work)