javascript跨浏览器操作xml

//跨浏览器获取xmlDom

 function getXMLDOM(xmlStr) {

     var xmlDom = null;

     if (typeof window.DOMParser != 'undefined') {

         xmlDom = (new DOMParser).parseFromString(xmlStr,'text/xml'); //创建xmlDom对象

         var errors = xmlDom.getElementsByTagName('parsererror');

         if(errors.length > 0) {

             throw new Error('XML格式有误:'+errors[0].textContent);

         }

         return xmlDom;

     } else if (typeof window.ActiveXObject != 'undefined') {

         var version = [

             'MSXML2.DOMDocument.6.0',

             'MSXML2.DOMDocument.3.0',

             'MSXML2.DOMDocument'

         ];

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

             try {

                 var xmlDom = new ActiveXObject(version[i]);

             } catch (e) {

                 //遇到错误跳过,继续执行try

             }

         }

         xmlDom.loadXML(xmlStr);

         if(xmlDom.parseError != 0) { //使用 !+ 号

             throw new Error('错误信息为:' + xmlDom.parseError.reason);

         }

         return xmlDom;

     } else {

         throw new Error('系统或浏览器不支持xmlDom对象!');

     }

     return xmlDom;

 }

/*
DOM2没有序列化XML的属性，XMLSerializer类型来帮助序列化XML字符串。
IE9、Safari、Chrome和Opera都支持这个类型。
*/

 function serializerXML(xmlDom) {

     var xml = null;

     if(typeof window.XMLSerializer != 'undefined') {//w3c的序列化

             var serializer = new XMLSerializer();

             xml = serializer.serializeToString(xmlDom);

     } else if(typeof xmlDom.xml != 'undefined') { //ie直接序列化

             xml = xmlDom.xml;

     }

     return xml;

 }

//跨浏览器获取xml单一节点

 function selectSingleNode(xmlDom,xpath) {

     var node = null;

     if(typeof xmlDom.evaluate != 'undefined') { //w3c

         var patt = /\[(\d+)\]/;

         var num = null;

         var flag = xpath.match(patt);

         if (flag) {

             num = parseInt(RegExp.$1) + 1;//w3c下标从1开始,如0加1

             xpath = xpath.replace(patt,'['+num+']'); //root/user[1]

         }

         var result = xmlDom.evaluate(xpath,xmlDom,null,XPathResult.FIRST_ORDERED_NODE_TYPE,null);

         if(result != null) {

             node = result.singleNodeValue; //w3c默认的下标是1

         }

     } else if (typeof xmlDom.selectSingleNode != 'undefined') {//ie中unknown而非 undefined

         node = xmlDom.selectSingleNode(xpath);

     }

     return node;

 }

//跨浏览器获取xml所有节点

 function selectNodes(xmlDom,xpath) {

     var nodes = [];

     if(typeof xmlDom.evaluate != 'undefined') { //w3c

         var patt = /\[(\d+)\]/;

         var num = null;

         var flag = xpath.match(patt);

         if(flag) {

             num = parseInt(RegExp.$1) + 1;

             xpath = xpath.replace(patt,'['+num+']');

         }

         var result = xmlDom.evaluate(xpath,xmlDom,null,XPathResult.ORDERED_NODE_ITERATOR_TYPE,null);

         var node = null;

         if(result != null) {

             while ((node = result.iterateNext()) !== null) {

                 nodes.push(node);

             }

         }

     } else if (typeof xmlDom.selectNodes != 'undefined') { //unkonwn

         nodes = xmlDom.selectNodes(xpath);

     }

     return nodes;

 }

 var xmlStr = '<root><name id="d1">du1</name><name id="d2">du2</name></root>';

 var xmlDom = getXMLDOM(xmlStr);

 var nodes = selectNodes(xmlDom,'root/name');

 //alert(nodes.length);

 //alert(serializerXML(xmlDom)); //序列化xmlStr

 //alert(serializerXML(selectSingleNode(xmlDom,'root/name[0]'))); //序列化单一节点

 alert(serializerXML(nodes[0]));//<name id="d1">du1</name>

 alert(serializerXML(nodes[1]));