By client script, you cannot pass a value from one aspx page to another as aspx page runs at server and javascript runs at client's end. To use client script to pass values, you need to persist the value in client side using cookies.
Here are several ways you can pass values,
1. Querystring
2. Cross Page Posting
3. Using Form's POST method to get access of request.forms value to next page
. Hidden fields
5. Session
6. Cache
7. Static object - not desirable
8.Cookies
Using Session will be more resource oriented. Si, I suggest to use cross page posting.
Here is the msdn link,
http://msdn.microsoft.com/en-us/library/ms178139(v=vs.100).aspx[
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Hope this helps.
cheers