c# code inside aspx page

hi all
i have a javascript in my aspx page like this:
<script language="javascript"
src='<%# "http://www.sth/feed/?Ad=1&row=" + DropDownList1.SelectedValue.ToString() + "&col=4" %>' ></script>


it wa row=2&col=4...  but i want the row to be selected from a DroDownList. but the code above Doesn't work.
how could i fix it?


thank you

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