Create linked time input - HTML/PHP/JAVASCRIPT

Question

I need to "link" the two input forms so if i select a certain time, the second input will not display times before the choosen one.

ex: I select 16:30, the second input displays: 17:00, 17:30, 18:00, etc...

sorry for my bad english. here's the code. I think i need to use JS to hide other objects but i don't know how to do it.

Thanks for help

<div class="input-group">
  <!--start time-->
  <span class="input-group-addon"><div class="ciao">Inizio</div></span>
  <select class="form-control" name="start">
    <?php $orari=h oursRange(12 * 3600, 20 * 3600, 30 * 60); 
          foreach ($orari as $key=>$value) { 
           echo "<option>$value</option>"; 
    } ?>
  </select>
</div>

<!--end time-->
<div class="input-group">
  <span class="input-group-addon"><div class="ciao">Fine</div></span>
  <select class="form-control" name="end">
    <?php foreach ($orari as $key=>$value) 
          { 
            echo "<option>$value</option>"; 
         } ?>
  </select>
</div>

Answer 1

I would suggest you look at jQuery Timepicker: http://jonthornton.github.io/jquery-timepicker/

Here is an example you can use with your code after downloading timepicker:

<div id="timepicker">
    Inizio: <input type="text" class="time start" name="start" />
    Fine: <input type="text" class="time end" name="end" />
</div>

<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script type="text/javascript" src="jquery.timepicker.js"></script>
<link rel="stylesheet" type="text/css" href="jquery.timepicker.css" />

<script type="text/javascript" src="lib/bootstrap-datepicker.js"></script>
<link rel="stylesheet" type="text/css" href="lib/bootstrap-datepicker.css" />
<script type="text/javascript" src="lib/site.js"></script>
<link rel="stylesheet" type="text/css" href="lib/site.css" />
<script src="http://jonthornton.github.io/Datepair.js/dist/datepair.js"></script>
<script src="http://jonthornton.github.io/Datepair.js/dist/jquery.datepair.js"></script>

<script>
    $('#timepicker .time').timepicker({
        'showDuration': true,
        'timeFormat': 'g:ia'
    });

    $('#timepicker').datepair();
</script>

Hope this helps!