W3cubDocs

/DOM

document.createNodeIterator

Returns a new NodeIterator object.

Syntax

var nodeIterator = document.createNodeIterator(root, whatToShow, filter);

Values

root

The root node at which to begin the NodeIterator's traversal.

whatToShow Optional

Is an optional unsigned long representing a bitmask created by combining the constant properties of NodeFilter. It is a convenient way of filtering for certain types of node. It defaults to 0xFFFFFFFF representing the SHOW_ALL constant.

Constant	Numerical value	Description
`NodeFilter.SHOW_ALL`	`-1` (that is the max value of `unsigned long`)	Shows all nodes.
`NodeFilter.SHOW_ATTRIBUTE`	`2`	Shows attribute `Attr` nodes. This is meaningful only when creating a `TreeWalker` with an `Attr` node as its root; in this case, it means that the attribute node will appear in the first position of the iteration or traversal. Since attributes are never children of other nodes, they do not appear when traversing over the document tree.
`NodeFilter.SHOW_CDATA_SECTION`	`8`	Shows `CDATASection` nodes.
`NodeFilter.SHOW_COMMENT`	`128`	Shows `Comment` nodes.
`NodeFilter.SHOW_DOCUMENT`	`256`	Shows `Document` nodes.
`NodeFilter.SHOW_DOCUMENT_FRAGMENT`	`1024`	Shows `DocumentFragment` nodes.
`NodeFilter.SHOW_DOCUMENT_TYPE`	`512`	Shows `DocumentType` nodes.
`NodeFilter.SHOW_ELEMENT`	`1`	Shows `Element` nodes.
`NodeFilter.SHOW_ENTITY`	`32`	Shows `Entity` nodes. This is meaningful only when creating a `TreeWalker` with an `Entity` node as its root; in this case, it means that the `Entity` node will appear in the first position of the traversal. Since entities are not part of the document tree, they do not appear when traversing over the document tree.
`NodeFilter.SHOW_ENTITY_REFERENCE`	`16`	Shows `EntityReference` nodes.
`NodeFilter.SHOW_NOTATION`	`2048`	Shows `Notation` nodes. This is meaningful only when creating a `TreeWalker` with a `Notation` node as its root; in this case, it means that the `Notation` node will appear in the first position of the traversal. Since entities are not part of the document tree, they do not appear when traversing over the document tree.
`NodeFilter.SHOW_PROCESSING_INSTRUCTION`	`64`	Shows `ProcessingInstruction` nodes.
`NodeFilter.SHOW_TEXT`	`4`	Shows `Text` nodes.

filter Optional

An object implementing the NodeFilter interface; its acceptNode() method will be called for each node in the subtree based at root which is accepted as included by the whatToShow flag to determine whether or not to include it in the list of iterable nodes (a simple callback function may also be used instead). The method should return one of NodeFilter.FILTER_ACCEPT, NodeFilter.FILTER_REJECT, or NodeFilter.FILTER_SKIP. See the Example.

Note: Prior to Gecko 12.0 (Firefox 12.0 / Thunderbird 12.0 / SeaMonkey 2.9), this method accepted an optional fourth parameter (entityReferenceExpansion) that is not part of the DOM4 specification, and has therefore been removed. This parameter indicated whether or not the children of entity reference nodes were visible to the iterator. Since such nodes were never created in browsers, this paramater had no effect.

Example

var nodeIterator = document.createNodeIterator(
    document.body,
    NodeFilter.SHOW_ELEMENT,
    function(node) {
        return node.nodeName.toLowerCase() === 'p' ? NodeFilter.FILTER_ACCEPT : NodeFilter.FILTER_REJECT;
    }
);
var pars = [];
var currentNode;

while (currentNode = nodeIterator.nextNode()) {
  pars.push(currentNode);
}

Browser Compatibility

Supported in FF 3.5+, Chrome 1+, Opera 9+, Safari 3+, IE9+, Edge

Specifications

DOM Level 2 Traversal: NodeIterator

Edit this page on MDN