find controls that have been selected in asp.net
<p>Hi I'm building a web application for a client with some unique controls and criteria.  One page involves a detailed search function consisting of about 100 combo boxes and listboxes.  What I am trying to do is do a foreach(control that has been changed/selected){} and feed it into a function to generate a query.  There are 100 but the user may only use three for a particular search ?  </p>

<p>I know there must be a way to do this.  Thanks in advance for the help </p>
