The TreeWalker
object represents the nodes of a document subtree and a position within them.
A TreeWalker
can be created using the Document.createTreeWalker()
method.
Properties
This interface doesn't inherit any property.
TreeWalker.root
Read only- Returns a
Node
representing the root node as specified when theTreeWalker
was created. TreeWalker.whatToShow
Read only- Returns an
unsigned long
being a bitmask made of constants describing the types ofNode
that must 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 ofunsigned long
)Shows all nodes. NodeFilter.SHOW_ATTRIBUTE
'2
Shows attribute Attr
nodes. This is meaningful only when creating aTreeWalker
with anAttr
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 aTreeWalker
with anEntity
node as its root; in this case, it means that theEntity
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 aTreeWalker
with aNotation
node as its root; in this case, it means that theNotation
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. TreeWalker.filter
Read only- Returns a
NodeFilter
used to select the relevant nodes. TreeWalker.expandEntityReferences
Read only '- Is a
Boolean
indicating, when discarding anEntityReference
its whole sub-tree must be discarded at the same time. TreeWalker.currentNode
- Is the
Node
on which theTreeWalker
is currently pointing at.
Methods
This interface doesn't inherit any method.
Note: in the context of a TreeWalker
, a node is visible if it exists in the logical view determined by the whatToShow
and filter
parameter arguments. (Whether or not the node is visible on the screen is irrelevant.)
TreeWalker.parentNode()
- Moves the current
Node
to the first visible ancestor node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, or if it is before that the root node defined at the object construction, returnsnull
and the current node is not changed. TreeWalker.firstChild()
- Moves the current
Node
to the first visible child of the current node, and returns the found child. It also moves the current node to this child. If no such child exists, returnsnull
and the current node is not changed. TreeWalker.lastChild()
- Moves the current
Node
to the last visible child of the current node, and returns the found child. It also moves the current node to this child. If no such child exists,null
is returned and the current node is not changed. TreeWalker.previousSibling()
- Moves the current
Node
to its previous sibling, if any, and returns the found sibling. If there is no such node, returnnull
and the current node is not changed. TreeWalker.nextSibling()
- Moves the current
Node
to its next sibling, if any, and returns the found sibling. If there is no such node,null
is returned and the current node is not changed. TreeWalker.previousNode()
- Moves the current
Node
to the previous visible node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, or if it is before that the root node defined at the object construction, returnsnull
and the current node is not changed. TreeWalker.nextNode()
- Moves the current
Node
to the next visible node in the document order, and returns the found node. It also moves the current node to this one. If no such node exists, returnsnull
and the current node is not changed.
Specifications
Specification | Status | Comment |
DOMThe definition of 'TreeWalker' in that specification. | Living Standard | Removed the expandEntityReferences property.
|
Document Object Model (DOM) Level 2 Traversal and Range SpecificationThe definition of 'TreeWalker' in that specification. | Obsolete | Initial definition. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
TreeWalker
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
currentNode
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
No support 4 — 21 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
No support 4 — 21 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes | |
filter
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
firstChild
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
lastChild
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
nextNode
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
nextSibling
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
parentNode
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
previousNode
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
previousSibling
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
root
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
whatToShow
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 4 |
IE
Full support 9 |
Opera
Full support 9 |
Safari
Full support 3 |
WebView Android
Full support 3 |
Chrome Android
Full support Yes |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3 |
Samsung Internet Android
Full support Yes |
Legend
- Full support
- Full support
- No support
- No support
- Deprecated. Not for use in new websites.'
- Deprecated. Not for use in new websites.
See also
- The creator method:
Document.createTreeWalker()
. - Related interfaces:
NodeFilter
,NodeIterator
.
TreeWalker by Mozilla Contributors is licensed under CC-BY-SA 2.5.