title: multiple checkbox dropdown onchange() not working
body: <p>Multiple Drop Down Checkbox not working properly. always getting first parameter as <code>undefined</code> and always <code>onchange</code> getting first checkbox value. </p>
  
  <pre><code>&lt;select name="multicheckbox[]" multiple="multiple" class="4colactive" onchange="selectsearch(this.selected,'property_type',this.value);"&gt;
      &lt;option value="AK"&gt;Alaska&lt;/option&gt;
      &lt;option value="AZ"&gt;Arizona&lt;/option&gt;
      &lt;option value="AR"&gt;Arkansas&lt;/option&gt;
      &lt;option value="CA"&gt;California&lt;/option&gt;
      &lt;option value="CO"&gt;Colorado&lt;/option&gt;
      &lt;option value="CT"&gt;Connecticut&lt;/option&gt;
      &lt;option value="DE"&gt;Delaware&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>my java script code which call when <code>onchange</code> dropdown.</p>
  
  <pre class="lang-js prettyprint-override"><code>function selectsearch(val2,val1,state_id){
      var title=state_id;
      alert(val2);
      alert(val1);
      alert(state_id);
      $.ajax({
          url: '&lt;?php echo base_url(); ?&gt;index.php/property/propertysearch',
          data: {'title':title,'name':val1,'status':val2 }, // change this to send js object
          type: "post",
          success: function(data){
              //document.write(data); just do not use document.write
              console.log(data);
              document.getElementById('search').innerHTML = data; 
              document.getElementById('search').style.display  = 'block'; 
              document.getElementById("search1").style.display = 'none';
          },
          error: function(){
              alert("Fail")
          }
      });
  }
  </code></pre>