JavaScript XMLをJSONに変換する方法

//加载xml数据
    function loadXml(str) {
        if (str == null) {
            return null;
        }
        var doc = str;
        try{
            doc = createXMLDOM();
            doc.async = false;
            doc.loadXML(str);
        }catch(e){
            doc = $.parseXML(str);
        }
        return doc;
    }

    //xml数据转成json对象的数据
    function xmlTojson(xmlObj, nodename, isarray){
        var obj = $(xmlObj);
        var itemobj = {};
        var nodenames = "";
        var getAllAttrs = function(node){//递归解析xml 转换成json对象
            var _itemobj = {};
            var notNull = false;
            var nodechilds = node.childNodes;
            var childlenght = nodechilds.length;
            var _attrs = node.attributes;
            var firstnodeName = "#text";
            try{
                firstnodeName = nodechilds[0].nodeName;
            }catch(e){

            }
            if((childlenght > 0 && firstnodeName != "#text") || _attrs.length > 0){
                var _childs = nodechilds;
                var _childslength = nodechilds.length;
                var _fileName_ = "";
                if(undefined != _attrs){
                    var _attrslength = _attrs.length;
                    for(var i = 0; i < _attrslength; i++){//解析xml节点属性
                        var attrname = _attrs[i].nodeName;
                        var attrvalue = _attrs[i].nodeValue;
                        _itemobj[attrname] = attrvalue;
                    }
                }
                for (var j = 0; j < _childslength; j++) {//解析xml子节点
                    var _node = _childs[j];
                    var _fildName = _node.nodeName;
                    if("#text" == _fildName){break;};
                    if(_itemobj[_fildName] != undefined){//如果有重复的节点需要转为数组格式
                        if(!(_itemobj[_fildName] instanceof Array)){
                            var a = _itemobj[_fildName];
                            _itemobj[_fildName] = [a];//如果该节点出现大于一个的情况 把第一个的值存放到数组中
                        }
                    }
                    var _fildValue = getAllAttrs(_node);
                    try{
                        _itemobj[_fildName].push(_fildValue);
                    }catch(e){
                        _itemobj[_fildName] = _fildValue;
                        _itemobj["length"] = 1;
                    }
                }
           }else{
                _itemobj = (node.textContent == undefined) ? node.text : node.textContent;
           }
           return _itemobj;
        };

        if(nodename){
            nodenames = nodename.split("/")
        }
        for(var i = 0;i < nodenames.length; i++){
            obj = obj.find(nodenames[i]);
        }
        $(obj).each(function(key, item){
            if(itemobj[item.nodeName] != undefined){
                if(!(itemobj[item.nodeName] instanceof Array)){
                    var a = itemobj[item.nodeName];
                    itemobj[item.nodeName] = [a];
                }
                itemobj[item.nodeName].push(getAllAttrs(item));
            }else{
                if(nodenames.length > 0){
                    itemobj[item.nodeName] = getAllAttrs(item);
                }else{
                    itemobj[item.firstChild.nodeName] = getAllAttrs(item.firstChild);
                }
            }
        });

        if(nodenames.length > 1){
            itemobj = itemobj[nodenames[nodenames.length-1]];
        }
        if(isarray && !(itemobj instanceof Array) && itemobj != undefined){
            itemobj = [itemobj];
        }
        return itemobj;
    }
    
    //实例测试
    var dataStr = ''
    var xmlObj = loadXml(dataStr);
    var jsonData = xmlTojson(xmlObj, 'userList/user', true);
    console.log(jsonData)