I need to build some strange thing

I've got a master page.
But i need to have the HTML of a page in a div.

So i've got a div:

<div id="page1"></div>

I should get the (generated) HTML code of this page in it:

defaultex.aspx?id=1

I can't use a i-frame because de size can change from 4000pixels height to 30 pixels height. And i need the full html without a height.

How can i do this ? Or is this possible in ASPX ? with a kind of include.
Thanks.
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