select an option and invoke onChange

[Di Wu]

Hello all,

Here is part of my HTML code:
   ...
   <SCRIPT type="text/javascript">
      function changeRole(id) {
         if (id!="" && id!="-1"){
            location = "Desktop?action=changeRole&id=" + id;
         }
      }
    </SCRIPT>

    <SELECT class="formElement" Name="roles" onChange="changeRole(this.options[selectedIndex].value)">
      <OPTION VALUE="-1" SELECTED>Current User</OPTION>
      <OPTION VALUE="">---Workgroups---</OPTION>
      <OPTION VALUE="385">Matrix</OPTION>
  </SELECT>&nbsp;

There is no form in this HTML. Could anyone give me help on how to change/get an option value and invoke the changeRole function in HttpUnit?

Thank you very much. Your help is really appreciated.

Di