<!DOCTYPE html>          
<html lang="en">
<head>
<meta charset="UTF-8">
<title>js实现xml转json</title>
<style type="text/css">
html,body{width:100%;height:100%;margin:0;}
</style>
</head>
<body>
<script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.js"></script>
<script type="text/javascript">
// Converts XML to JSON
// from: http://coursesweb.net/javascript/convert-xml-json-javascript_s2
function XMLtoJSON() {
var me = this; // stores the object instantce

// gets the content of an xml file and returns it in
me.fromFile = function(xml, rstr) {
// Cretes a instantce of XMLHttpRequest object
var xhttp = (window.XMLHttpRequest) ? new XMLHttpRequest() : new ActiveXObject("Microsoft.XMLHTTP");
// sets and sends the request for calling "xml"
xhttp.open("GET", xml ,false);
xhttp.send(null);

// gets the JSON string
var json_str = jsontoStr(setJsonObj(xhttp.responseXML));

// sets and returns the JSON object, if "rstr" undefined (not passed), else, returns JSON string
return (typeof(rstr) == 'undefined') ? JSON.parse(json_str) : json_str;
}

// returns XML DOM from string with xml content
me.fromStr = function(xml, rstr) {
// for non IE browsers
if(window.DOMParser) {
var getxml = new DOMParser();
var xmlDoc = getxml.parseFromString(xml,"text/xml");
}
else {
// for Internet Explorer
var xmlDoc = new ActiveXObject("Microsoft.XMLDOM");
xmlDoc.async = "false";
}

// gets the JSON string
var json_str = jsontoStr(setJsonObj(xmlDoc));

// sets and returns the JSON object, if "rstr" undefined (not passed), else, returns JSON string
return (typeof(rstr) == 'undefined') ? JSON.parse(json_str) : json_str;
}

// receives XML DOM object, returns converted JSON object
var setJsonObj = function(xml) {
var js_obj = {};
if (xml.nodeType == 1) {
if (xml.attributes.length > 0) {
js_obj["@attributes"] = {};
for (var j = 0; j < xml.attributes.length; j++) {
var attribute = xml.attributes.item(j);
js_obj["@attributes"][attribute.nodeName] = attribute.value;
}
}
} else if (xml.nodeType == 3) {
js_obj = xml.nodeValue;
}
if (xml.hasChildNodes()) {
for (var i = 0; i < xml.childNodes.length; i++) {
var item = xml.childNodes.item(i);
var nodeName = item.nodeName;
if (typeof(js_obj[nodeName]) == "undefined") {
js_obj[nodeName] = setJsonObj(item);
} else {
if (typeof(js_obj[nodeName].push) == "undefined") {
var old = js_obj[nodeName];
js_obj[nodeName] = [];
js_obj[nodeName].push(old);
}
js_obj[nodeName].push(setJsonObj(item));
}
}
}
return js_obj;
}

// converts JSON object to string (human readablle).
// Removes '\t\r\n', rows with multiples '""', multiple empty rows, ' "",', and " ",; replace empty [] with ""
var jsontoStr = function(js_obj) {
var rejsn = JSON.stringify(js_obj, undefined, 2).
replace(/(\\t|\\r|\\n)/g, '').replace(/"",[\n\t\r\s]+""[,]*/g, '').
replace(/(\n[\t\s\r]*\n)/g, '').replace(/[\s\t]{2,}""[,]{0,1}/g, '').
replace(/"[\s\t]{1,}"[,]{0,1}/g, '');
return (rejsn.indexOf('"parsererror": {') == -1) ? rejsn : 'Invalid XML format';
}


};

// creates object instantce of XMLtoJSON
var xml2json = new XMLtoJSON();
</script>

<script type="text/javascript">

var xmlstr = `<alexa ver="0.9" url="http://coursesweb.net/" home="0" aid="=">
<sd title="a" host="coursesweb.net">
<title>CoursesWeb: php, mysql, html, css, javascript, ajax, jquery, actionscript, flash</title>
<linksin num="1102"/>
<speed pct="51">4578</speed>
</sd>
<sd>
<popularity>5777</popularity>
<reach rank="5952"/>
<rank url="http://coursesweb.net/">6667</rank>
</sd>
</alexa>`;

// gets JSON object from a string with xml content
var objson = xml2json.fromStr(xmlstr);
console.log(objson);

// gets JSON string from a string with xml content
var strjson = xml2json.fromStr(xmlstr, 'string');
console.log(strjson);
</script>
</body>
</html>