title: Show/hide form fields based on a selection from a drop down menu
body: <p>I have this code but problem is that when the value is blank (option 1) states are shown up. How to hide it if the value is blank?</p>
  
  <pre><code>&lt;select id="country""&gt;
      &lt;option value="" disabled="disabled" selected="selected"&gt;PLEASE CHOOSE&lt;/option&gt;
      &lt;option value="USA"&gt;USA&lt;/option&gt;
      &lt;option value="UK"&gt;UK&lt;/option&gt;
      &lt;option value="IT"&gt;ITALY&lt;/option&gt;
  &lt;/select&gt;
  &lt;div id="states"&gt;
  &lt;/div&gt;
  
      $(document).ready(function(){
      $('#country').on('change', function() {
        if ( this.value == 'USA')
        {
          $("#states").show();
        }     
          else
        {
          $("#states").hide();
       }
      });
  });
  </code></pre>