title: jQuery UI Datepicker Add Days
body: <p>I'm attempting to create something of range system for booking rooms on a hotel website and I'm using jQuery UI Datepicker to allow the user to select their check in date. What I then want to do is create another field that's simple "Number of Nights" and have jQuery Datepicker take the check in date, add the number of nights, and set the resulting date as the value of a hidden input (in the correct date format). It would look something like this:</p>
  
  <pre><code>&lt;input type="text" name="arrivalDate" class="datepicker"&gt;
  &lt;input type="text" name="numOfNights"&gt;
  &lt;input type="hidden" name="departureDate" value="arrivalDate + number of nights"&gt;
  </code></pre>
  
  <p>Is this possible? Thanks in advance.</p>
  
  <p>(Note: The database I'll be "get"-ing from with this form is a little temperamental and I don't have access to it beyond just a few query-able values.)</p>