AJAX Webforms and PHP

[Nate1]

USing the code below can I create a system for filling a drop down box in ASP I have done this in PHP, but with webforms there are alot of tags by default, in PHP i would return just the <option>? tags. Im thinking that I need to approx this differently in ASP (VB)

   function createRequestObject() {
    var ro;
    var browser = navigator.appName;
    if(browser == "Microsoft Internet Explorer"){
       ro = new ActiveXObject("Microsoft.XMLHTTP");
     }else{
          ro = new XMLHttpRequest();
     }
      return ro;
    }

    var http = createRequestObject();


    function sndReq(Loc) {
        http.open('get','Page.aspx';
        http.onreadystatechange = handleResponse;
        http.send(null); 
        }

    function handleResponse() {
        if(http.readyState == 4){

        }
     }