title: success message afer submit an html form
body: <p>I have a simple <em>html</em> form like:</p>
  
  <pre><code>&lt;form id="form1" method="post" target="_self"&gt;
  &lt;input type="text" name="lastname"&gt;
  &lt;input type="submit" value="Register" /&gt;
  &lt;form&gt;
  </code></pre>
  
  <p>I want to replace the whole of this same page with just a success message
  from the server, which will also show 'lastname' that was send.
  Is there a simple way to do it with from the server side?
  (asp.net forms application)</p>
  
  <p>Thanks a lot </p>
  
  <p>Liron</p>