function CreatXmlDoc(obj){this.tagName=obj.tagName;this.properties = obj.properties;var children=obj.children.map(function(item){if(typeof item =="object"){item=new CreatXmlDoc(item)}return item})this.children=children;}function loadXMLDoc(dname) {try {//Internet ExplorerxmlDoc = new ActiveXObject("Microsoft.XMLDOM");} catch(e) {try {//Firefox, Mozilla, Opera, etc.xmlDoc = document.implementation.createDocument("", "", null);} catch(e) {alert(e.message)}}return xmlDoc;}CreatXmlDoc.prototype.render=function(){xmlDoc = loadXMLDoc();var xe1 = xmlDoc.createElement(this.tagName);for(var p in this.properties){xe1.setAttribute(p, this.properties[p]);}var children=this.children || [];children.forEach(function(child){var childEl=(child instanceof CreatXmlDoc)? child.render():xmlDoc.createTextNode(child)xe1.appendChild(childEl);})return xe1;}

// 封装调用函数

// 将json转成xml文档，再转成字符串
var xmlToString = function(eleJson) {var doc=new CreatXmlDoc(eleJson);SetupSerial=(new XMLSerializer()).serializeToString(doc.render());var reg = new RegExp(' xmlns="http://www.w3.org/1999/xhtml"',"g");// 替换转义字符var reg1 = new RegExp('&lt;',"g"); // <var reg2 = new RegExp('&gt;',"g"); // >var reg3 = new RegExp('&amp;',"g"); // &var reg4 = new RegExp('&apos;',"g"); // 'var reg5 = new RegExp('&quot;',"g"); // "SetupSerial=SetupSerial.replace(reg,"").replace(reg1, "<").replace(reg2, ">").replace(reg3, "&").replace(reg4, "'").replace(reg5, '"');return SetupSerial; }

var obj={tagName:'Setup',properties:{type:"text",name:"hahha",title:"哈哈"},children:[{tagName:'ProtocolList',children:[{tagName:'Protocol',children:[{tagName:'Name',children:["onvif"]}, {tagName:'UserName',children:["admin"]}, {tagName:'PassWord',children:["admin"]}, {tagName:'Port',children:["8000"]}, {tagName:'MediaPort',children:["8000"]}, ]},{tagName:'Protocol',children:[{tagName:'Name',children:["onvif"]}, {tagName:'UserName',children:["admin"]}, {tagName:'PassWord',children:["admin"]}, {tagName:'Port',children:["8000"]}, {tagName:'MediaPort',children:["8000"]}, ]},{tagName:'Protocol',children:[{tagName:'Name',children:["onvif"]}, {tagName:'UserName',children:["admin"]}, {tagName:'PassWord',children:["admin"]}, {tagName:'Port',children:["8000"]}, {tagName:'MediaPort',children:["8000"]}, ]},              ]},{tagName:'Function',children:[{tagName:'PlayBack',children:["onvif"]             },{tagName:'Other',children:["rtsp"] }]}]}SetupSerial = xmlToString(obj);
console.log(SetupSerial);

<Setup type="text" name="hahha" title="哈哈"><ProtocolList><Protocol><Name>onvif</Name><UserName>admin</UserName><PassWord>admin</PassWord><Port>8000</Port><MediaPort>8000</MediaPort></Protocol><Protocol><Name>onvif</Name><UserName>admin</UserName><PassWord>admin</PassWord><Port>8000</Port><MediaPort>8000</MediaPort></Protocol><Protocol><Name>onvif</Name><UserName>admin</UserName><PassWord>admin</PassWord><Port>8000</Port><MediaPort>8000</MediaPort></Protocol></ProtocolList><Function><PlayBack>onvif</PlayBack><Other>rtsp</Other></Function>
</Setup>