title: cannot clear textbox wtihin update panel
body: <p>I'm pretty new to update panels and would appreciate some help.  I have a form with a few textboxes and submit button.  Before the update panel, I would do a page validation on the button click event and if everything was okay, enter the date into a db and then clear two of the textboxes.  Then I added the update panel.  Now, the textboxes won't clear.  Everything else is working great.  Any help?</p>
  
  <pre><code>    &lt;asp:UpdatePanel ID="upForm" runat="server" ChildrenAsTriggers="false" 
          UpdateMode="Conditional"&gt;
      &lt;Triggers&gt;&lt;asp:AsyncPostBackTrigger ControlID="ddlMember"  
          EventName="SelectedIndexChanged" /&gt;&lt;/Triggers&gt;&lt;/asp:UpdatePanel&gt;
  
  CType(upForm.FindControl("txtAuth"), TextBox).Text = String.Empty  
  txtAuth.Text = String.Empty
  </code></pre>