XML Javascript parse problem (specific code question )

I'm using the following parser to parse xml

function parseXML(text) {
    var doc;

    if(window.DOMParser) {
        var parser = new DOMParser();
        doc = parser.parseFromString(text, "text/xml");
    }
    else if(window.ActiveXObject) {
        doc = new ActiveXObject("Microsoft.XMLDOM");
        doc.async = "false";
        doc.loadXML(text);
    }
    else {
        throw new Error("Cannot parse XML");
    }

    return doc;
}

I can't understand why it isn't working on my XML document, obtain开发者_C百科ed via AJAX.

Result via AJAX request:

X-Powered-By    PHP/5.2.11
Content-Length  887
Keep-Alive  timeout=5, max=95
Connection  Keep-Alive
Content-Type    text/xml

<?xml version="1.0" encoding="UTF-8"?>
<xml_test>wont work!</xml_test>

Test Code:

    var xml = parseXML(data);
    $(xml).find("xml_test").each(function()
    {
        console.info('found xml_test... never happen..');
    });

But if I use it like this it works nicely!

    var data = '<xml_test>works</xml_test>';
    var xml = parseXML(data);
    $(xml).find("xml_test").each(function()
    {
        alert('this works!');
    });

I know that this is a specific question but I would appreciate your help and/or suggestions...

Thanks in advance Pedro

If you use jQuery to request your resource, you should already get XML DOM document in case it was served with text/xml mime-type. Thus no need to parse.

If you're getting your XML via Ajax, there's no need to parse it because the browser will do it for you. Simply use the responseXML property of the XMLHttpRequest object, which will give you an XML document object. jQuery wraps this using "xml" for the dataType:

 $.ajax({
     type: "GET",
     url: "foo.xml",
     dataType: "xml",
     success: function(xml) {
         alert(xml.documentElement.nodeName);
     }
 });

I use this function and gives me good result:

var myLoadXml = function(s){

  var objxml = null;

  if(document.implementation && document.implementation.createDocument) {

     var objDOMParser = new DOMParser();
     objxml = objDOMParser.parseFromString(s, "text/xml");

  } else if (window.ActiveXObject) {

     objxml = new ActiveXObject('MSXML2.DOMDocument.3.0');
     objxml.async = false;
     objxml.loadXML(s);

  }

  return objxml;
};


var xml = myLoadXml(data);

$(xml).find("xml_test").each(function()
{
    console.info('found xml_test... never happen..');
});

EDIT Example

** EDIT II **

function parseXML(text) {
    var doc;

    if (typeof text == 'object'){ // check type of text
        return text; 
    }

    if(window.DOMParser) {
        var parser = new DOMParser();
        doc = parser.parseFromString(text, "text/xml");
    }
    else if(window.ActiveXObject) {
        doc = new ActiveXObject("Microsoft.XMLDOM");
        doc.async = "false";
        doc.loadXML(text);
    }
    else {
        throw new Error("Cannot parse XML");
    }

    return doc;
}

If you are using jQuery (as your test code suggests), you can simply pass the xml to it.

var xml = $(data);