You can perform various operations on items (control of visibility, checking of state, item existance etc.).
For their executing you have a number of methods and attributes.

For saving memory, we recommend to destruct dhtmlxForm instance at the end of form usage by unload method.

<body onload="doOnLoad()" onunload="doOnUnload()">
     <div id="myForm"></div>
  <script>
     var form;
     function doOnLoad() {
        form = new dhtmlXForm("myForm");
     }
     function doOnUnload() {
        form.unload();
        form = null;
     }
  </script>
</body>

Items operations