title: How know if ModelState contains errors
body: <p>When a form is posted in my controller, I make the following check:</p>
  
  <pre><code>if(ModelState.IsValid)
  </code></pre>
  
  <p>If the model is not valid, errors are added to the <code>ModelState</code>. The model is then passed to the view with validation summary. </p>
  
  <p>However, I want to check if the <code>ModelState</code> has errors from inside the jQuery <code>ready</code> handler, so that I can add some additional behavior if the form has errors. Is that possible?</p>