Jquery+Ajax+xml?й??Ч(?)

?? Jquery+Ajax+xml???е??xml?

???xml?(1000)???

<?xml version="1.0" encoding="utf-8"?>
<area Country="China">
 <province ID="1" provinceID="110000" province="">
  <City CityID="110100" City="?">
   <Piecearea PieceareaID="110101" Piecearea="" />
   <Piecearea PieceareaID="110102" Piecearea="" />
   <Piecearea PieceareaID="110103" Piecearea="" />
   <Piecearea PieceareaID="110104" Piecearea="" />
   <Piecearea PieceareaID="110105" Piecearea="" />
   <Piecearea PieceareaID="110106" Piecearea="?" />
   <Piecearea PieceareaID="110107" Piecearea="??" />
   <Piecearea PieceareaID="110108" Piecearea="" />
   <Piecearea PieceareaID="110109" Piecearea="?" />
   <Piecearea PieceareaID="110111" Piecearea="?" />
   <Piecearea PieceareaID="110112" Piecearea="?" />
   <Piecearea PieceareaID="110113" Piecearea="?" />
   <Piecearea PieceareaID="110114" Piecearea="?" />
   <Piecearea PieceareaID="110115" Piecearea="" />
   <Piecearea PieceareaID="110116" Piecearea="" />
   <Piecearea PieceareaID="110117" Piecearea="?" />
  </City>
<province>

?????/е?:

<h2>?</h2>
  ?:<select id="province" onchange="showcity()"><option value="0">-?-</option></select>
  :<select id="city" onchange="showdistrict()"><option value="0">-?-</option></select>
  :<select id="district"><option value="0">-?-</option></select>

//????洢?xml?,?xml
    var xmldom =null;
    //????
    function showprovince(){
      //?ajax?xml???
      $.ajax({
        url:'./ChinaArea.xml',
        //data:
        dataType:'xml',//??responseXML
        type:'get',
        success:function(msg){
          //?xml?xmldom
          xmldom = msg;
          //province ???
          var prov = $(msg).find('province');
          //??
          prov.each(function(k,v){
            var nm = $(this).attr('province');
            var id = $(this).attr('provinceID');
            //?????
            $('#province').append("<option value="+id+">"+nm+"</option>");
          });
        }

      });
    }
    //????  
    $(function(){
      showprovince();
    });
    function showcity(){
      //? ? id
      var pid = $('#province option:selected').val();
      //xmldom? ?????
      var xml_province = $(xmldom).find('province[provinceID='+pid+']');
      // ??н?
      var city = $(xml_province).find('City');
      //????????
      $('#city').empty();
      $('#city').append('<option value="0">-?-</option>');
      //?
      city.each(function(k,v){
        var nm = $(this).attr('City');
        var id = $(this).attr('CityID');
        $('#city').append('<option value='+id+'>'+nm+'</option>');
      });
    }
    //??showcity()??
    function showdistrict(){
      //?  id
      var cid = $('#city option:selected').val();
      //xmldom? ??н?
      var xml_city = $(xmldom).find('City[CityID='+cid+']');
      // ??е?
      var district = $(xml_city).find('Piecearea');
      $('#district').empty();
      $('#district').append('<option value="0">-?-</option>');
      district.each(function(k,v){
        var nm = $(this).attr('Piecearea');
        var id = $(this).attr('PieceareaID');
        $('#district').append('<option value='+id+'>'+nm+'</option>');
      });
    }

?Jquery+Ajax+xml?й??Ч(?)С??????ο????????