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TreeWalker.whatToShow

The TreeWalker.whatToShow read-only property returns an unsigned long being a bitmask made of constants describing the types of Node that must to be presented. Non-matching nodes are skipped, but their children may be included, if relevant. The possible values are:

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.

Syntax

nodeTypes = treeWalker.whatToShow;

Example

var treeWalker = document.createTreeWalker(
    document.body,
    NodeFilter.SHOW_ELEMENT + NodeFilter.SHOW_COMMENT + NodeFilter.SHOW_TEXT,
    { acceptNode: function(node) { return NodeFilter.FILTER_ACCEPT; } },
    false
);
if( (treeWalker.whatToShow == NodeFilter.SHOW_ALL) ||
    (treeWalker.whatToShow % (NodeFilter.SHOW_COMMENT*2)) >= NodeFilter.SHOW_COMMENT) {
    // treeWalker will show comments
}

Specifications

Specification	Status	Comment
DOM The definition of 'TreeWalker.whatToShow' in that specification.	Living Standard	No change from Document Object Model (DOM) Level 2 Traversal and Range Specification
Document Object Model (DOM) Level 2 Traversal and Range Specification The definition of 'TreeWalker.whatToShow' in that specification.	Obsolete	Initial definition.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	1	Yes	4	9	9	3

	Mobile
	Android webview	Chrome for Android	Edge Mobile	Firefox for Android	Opera for Android	iOS Safari	Samsung Internet
Basic support	3	Yes	Yes	4	9	3	?

TreeWalker.whatToShow

Syntax

Example

Specifications

Browser compatibilityUpdate compatibility data on GitHub

See also