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XPathResult.ORDERED_NODE_ITERATOR_TYPE

XPathResult.ORDERED_NODE_ITERATOR_TYPE,

null);

var aNodes = new Array;

if (oResult != null) {

var oElement = oResult.iterateNext();

while(oElement) {

aNodes.push(oElement);

oElement = oResult.iterateNext();

}

return aNodes;

};

The

selectNodes()

method is added to the

Element

class to mimic the behavior in IE. When

evaluate()

is called, it uses the

this

keyword as the context node (which is also how IE works). Then, a result array

(

aNodes

) is filled with all the matching nodes. You can use this new method like so:

var aNodes = oXmlDom.documentElement.selectNodes(“employee/name”);

for (var i=0; i < aNodes.length; i++) {

alert(aNodes[i].xml);

}

If you specify a snapshot result type (either ordered or unordered), you must use the

snapshotItem()

and

snapshotLength()

methods, as in the following example:

var oEvaluator = new XPathEvaluator();

var oResult = oEvaluator.evaluate(“employee/name”, oXmlDom.documentElement, null,

XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);

if (oResult != null) {

for (var i=0; i < oResult.snapshotLength; i++) {

alert(oResult.snapshotItem(i).tagName);

}

In this example,

snapshotLength

returns the number of nodes in the snapshot and

snapshotItem()

returns the node in a given position in the snapshot (similar to

length

and

item()

in a

NodeList

The

XPathResult.FIRST_ORDERED_NODE_TYPE

result returns the first matching node, which is accessi-

ble through the

singleNodeValue

property:

var oEvaluator = new XPathEvaluator();

var oResult = oEvaluator.evaluate(“employee/name”, oXmlDom.documentElement, null,

XPathResult.FIRST_ORDERED_NODE_TYPE, null);

alert(oResult.singleNodeValue.xml);

As you may have guessed, this code can be used to mimic the IE

selectSingleNode()

method:

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XML in JavaScript

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