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The NodeIterator
interface represents an iterator over the members of a list of the nodes in a subtree of the DOM. The nodes will be returned in document order.
A NodeIterator
can be created using the Document.createNodeIterator()
method, as follows:
var nodeIterator = document.createNodeIterator(root, whatToShow, filter);
Properties
This interface doesn't inherit any property.
NodeIterator.root
Read only- Returns a
Node
representing the root node as specified when theNodeIterator
was created. NodeIterator.whatToShow
Read only- Returns an
unsigned long
being a bitmask made of constants describing the types ofNode
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 ofunsigned long
)Shows all nodes. NodeFilter.SHOW_ATTRIBUTE
2
Shows attribute Attr
nodes. This is meaningful only when creating aNodeIterator
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 aNodeIterator
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 aNodeIterator
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. NodeIterator.filter
Read only- Returns a
NodeFilter
used to select the relevant nodes. NodeIterator.expandEntityReferences
Read only- Is a
Boolean
indicating if, when discarding anEntityReference
its whole sub-tree must be discarded at the same time. NodeIterator.referenceNode
Read only- Returns the
Node
to which the iterator is anchored. NodeIterator.pointerBeforeReferenceNode
Read only- Returns a
Boolean
flag that indicates whether theNodeIterator
is anchored before, the flag beingtrue
, or after, the flag beingfalse
, the anchor node.
Methods
This interface doesn't inherit any method.
NodeIterator.detach()
- This operation is a no-op. It doesn't do anything. Previously it was telling the engine that the
NodeIterator
was no more used, but this is now useless. NodeIterator.previousNode()
- Returns the previous
Node
in the document, ornull
if there are none. NodeIterator.nextNode()
- Returns the next
Node
in the document, ornull
if there are none.
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'NodeIterator' in that specification. |
Living Standard | Added the referenceNode and pointerBeforeReferenceNode properties.Removed the expandEntityReferences property.The method detach() has been changed to be a no-op.The methods previousNode() and nextNode() don't raise an exception any more. |
Document Object Model (DOM) Level 2 Traversal and Range Specification The definition of 'NodeIterator' in that specification. |
Recommendation | Initial definition. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 1.0 | 3.5 (1.9.1) | 9.0 | 9.0 | 3.0 |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | (Yes) | 1.0 (1.9.1) | (Yes) | 9.0 | 3.0 |
See also
- The creator method:
Document.createNodeIterator()
. - Related interfaces:
NodeFilter
,TreeWalker
.