in web applications, untill you are not on Default1.aspx. you can not access the page members.. from another page (Default2.aspx), because the page (and its members) are not yet initialised.
but you can access your previous page with cross page posting. means while you land on Default1.aspx redirected from Default2.aspx, then you can access Default2.aspx's last state.
follow the link to know how to use cross page posting.
http://msdn.microsoft.com/en-us/library/ms178139.aspx[
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