js调用xml生成树

js，页面，xml都在同一个文件夹中的
js里是这样写的：
               var dom = new ActiveXObject("Microsoft.XMLDOM");    //实例化dom对象
                dom.async = false;//加载xml文件                              
                dom.load("true.xml"); 
                if(dom == null) 
              { 
                    //window.location.href='index.aspx'; 
                   return; 
              } 
              //获得根接点 
                    var node = dom.documentElement.childNodes;  这里为空                      
                     for(var i=0;i<node.length;i++)
                    {
                        var title = node[i].childNodes[0].text;            
                         var content = node[i].childNodes[1].text;
                        var date = node[i].childNodes[2].text;
                        data.push({title:title,content:content,date:date});                       
  }
              
             
怎么加载xml呢
希望大家帮帮忙