title: Find all UserControls of a certain type on a page, possibly using LINQ?
body: <p>I have created a base user control (BaseUserControl) class that is implemented by all my user controls. In that class I have a property that contains a collection of JavaScript URL references.  What is the best way to parse a page for that type of user control? </p>
  
  <p>I experimented using LINQ, but I don’t think I can query the Controls collection with it:</p>
  
  <pre><code>var controls = (from c in page.Controls where c is BaseUserControl)
  foreach(control in controls){
       var javascript = control.JavaScriptReference
  }
  </code></pre>