Getting node value from XML string using javascript

Question

I am trying to retrieve the 'code' and the 'value' from an XML string.

I have the following XML string:

<items>
    <item>
            <id>55</id>
            <attributes>
                <attribute>
                    <code>ID</code>
                    <value><![CDATA[55]]></value>
                </attribute>
                <attribute>
                    <code>Chip_ID</code>
                    <value><![CDATA[1]]></value>
                </attribute>
                <attribute>
                    <code>FilterKey</code>
                    <value><![CDATA[5]]></value>
                </attribute>
                <attribute>
                    <code>DateTime</code>
                    <value><![CDATA[22/12/2014 12:21:25]]></value>
                </attribute>
            </attributes>
    </item>
</items>

I then have the following javaScript to identify each node:

var xmlDocument = new ActiveXObject('Microsoft.XMLDOM');
xmlDocument.async = false;
xmlDocument.loadXML(pXML);

var oFirstNode = xmlDocument.documentElement;

var item = oFirstNode.childNodes[0]; //10 of these and they represent the items
 //alert("1 "+item.nodeName);

var ID = item.childNodes[0]; //one of these for each level-ID - NO CHILDREN
var attributes = item.childNodes[1]; //one of these for each level-attributes
//alert("2 " + ID.nodeName);
//alert("2 " + attributes.nodeName);

var attribute = attributes.childNodes[0];//4 of these for each level and they all have 2 children-code and value
//alert("3 " + attribute.nodeName);

var code = attribute.childNodes[0];
var value = attribute.childNodes[1];

alert(code.nodeName);
alert(value.nodeName);

I know I am at the correct node as the alert boxes are all giving the expected values.

I now want to retrieve the text for 'code' and 'value' eg the first entry should return code = ID value = ![CDATA[55]]

I have tried:

alert(code.nodeValue);
alert(value.nodeValue);

but they are both coming back null.

score 7 · Answer 1 · edited May 23 '17 at 12:00

7

The .nodeValue property of a DOM element is always null.

Use .textContent instead.

alert(code.textContent);

I would also suggest using DOM traversal methods that don't require sifting through each individual child node by index:

var attributes = item.getElementsByTagName("attribute"); // should contain 4 elements

See also: nodeValue vs innerHTML and textContent. How to choose?

edited May 23 '17 at 12:00

Community

1
1

answered Dec 22 '14 at 14:51

JLRishe

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still no luck, it will not recognise getElementsByTagName – Dec 22 '14 at 15:10
@user2970105 `code.textContent` seems to be working here: http://jsfiddle.net/o3cp2wc5/ (I'm using jQuery to parse the XML since my browser doesn't support ActiveXObject). What version of IE are you using? – JLRishe Dec 22 '14 at 15:28
@user2970105 And here is an example of using `.getElementsByTagName()` to select elements: http://jsfiddle.net/onjs7kLm/ – JLRishe Dec 22 '14 at 15:33

score 0 · Answer 2 · answered Dec 22 '14 at 15:40

I found the answer. For some reason it is treating the value inside the tag as a child of the element, and so nodeValue returns the value I want. Below is my working solution:

            var xmlDocument = new ActiveXObject('Microsoft.XMLDOM');
            xmlDocument.async = false;
            xmlDocument.loadXML(pXML);

            var oFirstNode = xmlDocument.documentElement;

                var item = oFirstNode.childNodes[0]; //10 of these and they represent the items

                var ID = item.childNodes[0]; //one of these for each level-ID - NO CHILDREN
                var attributes = item.childNodes[1]; //one of these for each level-attributes

                alert(attributes.childNodes.length);

                    var attribute = attributes.childNodes[0];//4 of these for each level and they all have 2 children-code and value
                    //alert("3 " + attribute.nodeName);

                    var code = attribute.childNodes[0];
                    var value = attribute.childNodes[1];

                    alert(code.childNodes[0].nodeValue)
                    alert(value.childNodes[0].nodeValue)

            }

Getting node value from XML string using javascript

2 Answers2