Ignoring empty XML nodes in JavaScript

Question

I'm loading in an XML file in JavaScript, and once I've done that, I'm iterating through all of the Document's childNodes , which are all of the XML elements in the document. The problem that I'm having is that I need to ignore elements which are just not real elements, but rather newlines, tabs, etc. Right now I'm doing the following:

for (var i = 0; i < childList.length; i++)
{
    switch (childList[i].nodeType)
    {
        case 1: // Node.ELEMENT_NODE
            /* snip */
            break;
        case 3: // Node.TEXT_NODE
        case 8: // Node.COMMENT_NODE

            // Ensure the node is a valid node, and not newlines, tabs, etc
            if (!nodeEmpty(childList[i].nodeValue)
            {
                // do stuff
            }

            break;
    }
}

function nodeEmpty(nodeValue)
{
    var isEmpty = true;
    var length = nodeValue.length;
    for (var i = 0; i < length; i++)
    {
        if (nodeValue[i] != ' ' && nodeValue[i] != '\n' && nodeValue[i] != '\t')
        {
            isEmpty = false;
            break;
        }
    }

    return isEmpty;
}

But this seems like a very non-elegant way of achieving this. Is there a better way of doing this?

Answer 1

/**
 * xmlsimplify simplifies an XML object by copying it into a
 * javascript object with only a subset of the attributes of the original.
 * This makes it suitable for output as JSON, or for further processing by
 * other functions.

 * @param {Object} xml
 * @param {Boolean} strip if true, strip empty (whitespace) nodes
 */
var xmlsimplify = function(xml, strip) {
    var obj = {};
    if (typeof xml === "string") {
        xml = getXmlDocument(xml);
    }
    var traverse = function(node) {
        var i, l, n, a, j;
        if (node.nodeType) {
            var o = {};
            switch (node.nodeType) {
            case 1:
                //element node;
                o = {
                    nodeName: node.nodeName
                }; //record nodename
                for (i = 0, l = node.attributes.length, n = node.attributes; i < l; i++) { //append attributes
                    a = traverse(n.item(i));
                    for (j in a) {
                        if (a.hasOwnProperty(j)) {
                            o[j] = a[j];
                        }
                    }
                }
                if (node.childNodes.length) {
                    o.childNodes = [];
                    for (i = 0, l = node.childNodes.length, n = node.childNodes; i < l; i++) {
                        a = traverse(n.item(i));
                        if (a !== null) {
                            o.childNodes.push(a);
                        }
                    }
                    if (o.childNodes.length === 0) {
                        delete o.childNodes;
                    }
                }
                break;
            case 2:
                //attribute node
                o[node.nodeName] = node.nodeValue; //return an attribute object
                break;
            case 3:
                //text node
                //strip empty nodes
                if (node.nodeValue.match(/[^\s]/) && (strip === true)) {
                    o = node.nodeValue;
                } else {
                    o = null;
                }
                if (strip !== true) {
                    o = node.nodeValue;
                }
                break;
            case 4:
                //cdata section node
                o = node.nodeValue;
                break;
            case 9:
                //document node;
                o = traverse(node.firstChild);
                break;
            case 10:
                o = traverse(node.nextSibling);
                break;
            }
        }
        return o;
    };
    obj = traverse(xml);
    return obj;
};

Answer 2

function btn2Click() {
    try{
        ConObj = CreateXMLObj();
        ConObj.onreadystatechange = function () {
        if (this.readyState == 4 && this.status == 200) {            
            xmlObj = this.responseXML;
            oTitle = xmlObj.getElementsByTagName('TITLE');
            oYear = xmlObj.getElementsByTagName('YEAR');
            txt = "<center><table border=2>"; 
            for (i = 0; i < oTitle.length ; i++) {
                txt += "<TR><TD>" + setNA(oTitle[i].childNodes) + "</TD><TD>" + setNA(oYear[i].childNodes) + "</TD> </TR>";
                              }
              document.getElementById("demo").innerHTML = txt; alert('stage1');
        }   
        
    };
    ConObj.open("GET", "AjaxManager.aspx?cmd=ajaxXML", true);
    ConObj.send();
    } catch (e) {
        alert(e.toString);
    }
}

    

function setNA(value) {
    name = "NA";
    if (value.length > 0)
        name = value[0].nodeValue;
    return name;
}