Multiple forms

I have two forms, one that is using the asp.net controls and another one that will be using the old fashioned way.
The old fashioned form is just carrying whatevers in the textbox and carrying the value over to another page in the querystring, all I want to know is how to write it, here's what I have at the moment:
<form method="post" action="search.aspx?terms=<% Response.Write(SearchCriteria); %>" enctype="multipart/form-data">
<input id="SearchCriteria" name="SearchCriteria" type="text" />
<input id="SearchBtn" type="submit" value="Search Intranet" />   
</form>
I don't know how to declare the value SearchCriteria.


Can anyone shed any light?


Thanks in advance




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