jquery解析xml

$.ajax({

                     url:url,

                     type:"POST",

                     //data:params,

                     dataType: "xml",

                     async: false,

                     success:function(data){

                            //alert(userid);

                            $(data).find("Root").each(function(i){

                                   var length=$(this).children("PhoneBookCard").length;       //所有对象的长度象

                                   for(var i=0;i<length;i++){

                                          var cardId=$($(this).children("PhoneBookCard").get(i)).find("cardId").text();        //每一个对象下面的节点对

                                          alert(cardId)

                                   }

                            });

//上面兼容所有浏览器

if(null!=data){

                    &