title: Getting Id of a .net dropdownlist in javascript on client click
body: <p>I need to get the ID of a dropdownlist (ASP.Net Control) So that I can tell if an item has been selected.</p>
  
  <p>Right now I am trying to just write the count of the dropdownlist to an alert box as follows:</p>
  
  <pre><code>OnClientClick="alert(document.getElementID('&lt;%=ListBox1.ClientID %&gt;').options.length)
  </code></pre>
  
  <p>The error I get is 'document required.'</p>