XML実践攻略編 第4巻：メニュー連携

<?xml version="1.0" encoding="gb2312"?>
<China>
  <State id="1" name="江西">
    <City>九江</City>
    <City>南昌</City>
    <City>庐山</City>
    <City>景德镇</City>
  </State>
  <State id="2" name="北京">
    <City>北京西</City>
    <City>居庸关</City>
    <City>清华园</City>
    <City>周口店</City>
  </State>
  <State id="3" name="福建">
    <City>福州</City>
    <City>厦门</City>
    <City>漳州</City>
  </State>
  <State id="4" name="甘肃">
    <City>兰州</City>
    <City>洛门</City>
    <City>嘉峪关</City>
  </State>
  <State id="5" name="广东">
    <City>广州</City>
    <City>深圳</City>
    <City>东莞</City>
    <City>石牌</City>
  </State>
  <State id="6" name="安徽">
    <City>合肥</City>
    <City>黄山</City>
    <City>九龙岗</City>
    <City>马鞍山</City>
  </State>
</China>

function ChooseState()
{
  var source;
  var sourceName = "Citys.xml";
  var source = new ActiveXObject('Microsoft.XMLDOM');   //创建一个 MSXML解析器实例
  source.async = false;
  source.load(sourceName);   //装入XML文档
  root = source.documentElement;   //设置文档元素为根节点元素
  sortField=root.selectNodes("//@name");   //搜索属性中含有name的所有节点
  for(var i=0;i<sortField.length;++i)   //增加省份名称到下拉列表
  {
    var oOption = document.createElement(&#39;OPTION&#39;);
    oOption.text = " "+sortField[i].text+" ";
    oOption.value = sortField[i].text;
     form1.SelState.options.add(oOption); 
  }
   ChooseCity();
}

function ChooseCity()
{
  x=form1.SelState.selectedIndex;   //读取省份下拉框的当前选项
  y=form1.SelState.options[x].value;
  sortField=root.selectNodes("//State[@name='"+y+"']/City&q uot;);   //搜索name属性值等于
参数y的State节点下的所有city节点
  for(var i=form1.SelCity.options.length-1;i>=0;--i)   //撤消原来的列表项
  {
    form1.SelCity.options.remove(i)
  }
  for(var i=0;i<sortField.length;++i)   //增加城市名称到下拉列表
  {
    var oOption = document.createElement(&#39;OPTION&#39;);
    oOption.text = " "+sortField[i].text+" ";
    oOption.value = sortField[i].text;
    form1.SelCity.options.add(oOption); 
  }
}