title: Asp:RadioButtonList still posts back to server even when client validation fails?
body: <p>This query is related to <a href="https://stackoverflow.com/questions/259850/javascript-multiple-client-side-validations-on-same-event">this</a> one I asked yesterday.
  I have a radio button list on my asp.net page defined as follows:    </p>
  
  <pre><code>&lt;asp:RadioButtonList ID="rdlSortBy" runat="server" RepeatDirection="Horizontal" RepeatLayout="Flow" AutoPostBack="True" &gt;
         &lt;asp:ListItem Selected="True"&gt;Name&lt;/asp:ListItem&gt;
          &lt;asp:ListItem&gt;Staff No&lt;/asp:ListItem&gt;
  &lt;/asp:RadioButtonList&gt;
  </code></pre>
  
  <p>On the client-side, am doing the following validations:</p>
  
  <pre><code>rdlSortBy.Attributes("onclick") = "javascript:return prepareSave() &amp;&amp; prepareSearch();"
  </code></pre>
  
  <p>The problem is that the Javascript validation runs as expected.
  A message is displayed and I expect to remain on the page until user has saved the changes, instead the page is posted back and effectively I am loosing unsaved changes.</p>
  
  <p>What could be going wrong?</p>