title: how to fill two textbox via one datetimepicker
body: <p>I have two Texbox with datetime type, I want to fill both of them with one Datetimepicker. I mean first textbox is start date and second textbox is end date for project, default period for each project is 30 days. when I select 3/24/2015 via datetime picker first textbox should be 3/24/2015 and second text box automatically should be 4/24/2015 . how can I do this?</p>
  
  <p>this is my code :</p>
  
  <pre><code>&lt;input type="text" onclick="displayDatePicker('start', this, 'ymd')"&gt;
  </code></pre>