title: .Net user control cause an unexpected postback
body: <p>Hi I am a user control to trigger ActiveStepIndex change of a wizard on the main aspx page. </p>
  
  <p>The wizard control is inside the update panel.So if I trigger ActiveStepIndex from the aspx page, then the postback will only happen within the update panel. However if I trigger ActiveStepIndex from the user control, then the postback will happen in the whole page.</p>
  
  <p>Codes from user control:</p>
  
  <pre><code>Wizard mainWizard = Parent.FindControl("wizBlindOrder") as Wizard;
  mainWizard.ActiveStepIndex = 2;
  </code></pre>
  
  <p>I don't want the whole page to be refreshed (postback) when I trigger ActiveStepIndex from the user control, can anyone help me out? Thanks!</p>