title: Implode 3 select values into one field error
body: <p>I'm currently trying to place 3 select values into one field. I'm trying to do this by imploding the values; however i'm getting an error saying:</p>
  
  <blockquote>
    <p>"Warning: implode() [function.implode]: Invalid arguments passed" </p>
  </blockquote>
  
  <p>Updated Version</p>
  
  <pre><code>&lt;script&gt;
  function datepopulate(){
  var day = document.getElementById('airdate_day').value;
  var month = document.getElementById('airdate_month').value;
  var year = document.getElementById('airdate_year').value;
  
  var completedate = day+'-'+month+'-'+year;
  document.getelementById('episode_airdate').value = completedate;
  return true;
      }
  &lt;/script&gt;
          &lt;?php
  for($i=1910; $i&lt;=2012; $i++)
      $years[]=$i;
  
      echo '&lt;select id="airdate_year" onChange="javascript:datepopulate();" style="width:50px; float:left; margin-right:10px;"&gt;';
                          echo '&lt;option value=""&gt;' . __("2012" ) . '&lt;/option&gt;';
          foreach($years as $year){
                              $selected = '';
                              echo '&lt;option value="' . $year . '" ' . $selected . '&gt;' . $year . '&lt;/option&gt;';
                          }
                      echo '&lt;/select&gt;';
  
  
                      for($i=1; $i&lt;=12; $i++)
                          $months[]=$i;
  
                      echo '&lt;select id="airdate_month" onChange="javascript:datepopulate();" style="width:50px; float:left; margin-right:10px;"&gt;';
                          echo '&lt;option value=""&gt;' . __("0" ) . '&lt;/option&gt;';
                          foreach($months as $month){
                              $selected = '';
                              echo '&lt;option value="' . $month . '" ' . $selected . '&gt;' . $month . '&lt;/option&gt;';
                          }
                      echo '&lt;/select&gt;';
  
  
                      for($i=1; $i&lt;=31; $i++)
                          $days[]=$i;
  
                      echo '&lt;select name="airdate_day" id="airdate_day" onChange="javascript:datepopulate();"  style="width:50px; float:left; margin-right:10px;"&gt;';
                          echo '&lt;option value=""&gt;' . __("10" ) . '&lt;/option&gt;';
                          foreach($days as $day){
                              $selected = '';
                              echo '&lt;option value="' . $day . '" ' . $selected . '&gt;' . $day . '&lt;/option&gt;';
                          }
                      echo '&lt;/select&gt;';
                      ?&gt; 
              &lt;input type="hidden" name="episode_airdate[]" id="episode_airdate[]"  class="airdate regular-text" value="" /&gt;
  </code></pre>