Efficiently get all client form data for manipulating duuring raisecallback

Hi, I'm trying to get most of the data I have on my web page, to update a query during an asp 2.0 raisecallback event. I've tried Request.Form with no luck. I've got the html (sent in raisecallback parameter) using 2 div tag's innerhtml. Can someone tell me an efficient method to use to get all this data for updating - Do I have to parse from the callback string (eventArgument) & if so can I use a reader of somekind, or is there a better way? Please provide example & thanks in advance for any help!!
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