title: Wix. Conditionally set text property of the control
body: <p>I have previously installed app (version 1.0)
  Now I have to change the installer to upgrade app to 2.0 version. But I want to set all data specified by user on the previous installation. </p>
  
  <p>How can I conditionally fill text field in the wizard if I have all data in some properties.</p>
  
  <p>Something like:</p>
  
  <pre><code>&lt;?if &lt;![CDATA[ISUPGRADE]]&gt; ?&gt;
        &lt;Property Id="Account" Value="[Account_From_Registry]" /&gt;
        &lt;Property Id="Password" Value="******" /&gt;
  &lt;?endif?&gt;
  
  &lt;Control Id="Account" Type="Edit" Text="[Account]" /&gt;
  &lt;Control Id="Password" Type="Edit" Text="[Password]" /&gt;
  </code></pre>