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previousNode

var node3 = iterator.previousNode();

alert(node1 == node3); ///outputs “true”

For example, suppose you wanted to list all elements contained within a specific

<div/>

inside of a

specified area on an HTML page. The following code accomplishes this:

<html>

<head>

<title>NodeIterator Example</title>

var iterator = null;

function makeList() {

var oDiv = document.getElementById(“div1”);

iterator = document.createNodeIterator(oDiv,

NodeFilter.SHOW_ELEMENT, null, false);

var oOutput = document.getElementById(“text1”);

var oNode = iterator.nextNode();

while (oNode) {

oOutput.value += oNode.tagName + “\n”;

oNode = iterator.nextNode();

}

</script>

</head>

<body>

<p>Hello <b>World!</b></p>

<ul>

</ul>

</div>

</html>

When the button is clicked, the

is filled with the tag names of the elements contained in

div1

But suppose you don’t want to include

<p/>

elements in the results. This can’t be accomplished just by

using the

whatToShow

argument. In this case, you need a custom

NodeFilter

object.

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DOM Basics

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