DOM
SourceNodeIterator and TreeWalker objects can be used to filter and traverse node trees.
Each NodeIterator and TreeWalker object has an associated active flag to avoid recursive
invocations. It is initially unset.
Each NodeIterator and TreeWalker object also has an associated root (a node), a whatToShow (a bitmask), and a filter (a callback).
To filter a node node within
a NodeIterator or TreeWalker object traverser, run these steps:
In all current engines.
Firefox3.5+Safari3+Chrome1+ Opera9+Edge79+ Edge (Legacy)12+IE9+ Firefox for Android4+iOS Safari3+Chrome for Android18+Android WebView1+Samsung Internet1.0+Opera Mobile10.1+
[Exposed=Window]
interface NodeIterator { [SameObject] readonly attribute Node root; readonly attribute Node referenceNode; readonly attribute boolean pointerBeforeReferenceNode; readonly attribute unsigned long whatToShow; readonly attribute NodeFilter? filter; Node? nextNode(); Node? previousNode(); undefined detach();
};
NodeIterator objects can be created using the createNodeIterator() method on Document objects.
Each NodeIterator object has an associated iterator collection, which is a collection rooted at the NodeIterator object’s root, whose
filter matches any node.
Each NodeIterator object also has an associated reference (a node) and pointer before reference (a boolean).
As mentioned earlier, NodeIterator objects have an associated active flag, root, whatToShow, and filter as well.
The NodeIterator pre-removing steps given a nodeIterator and toBeRemovedNode, are as follows:
In all current engines.
Firefox3.5+Safari3+Chrome1+ Opera9+Edge79+ Edge (Legacy)12+IE9+ Firefox for Android4+iOS Safari3+Chrome for Android18+Android WebView1+Samsung Internet1.0+Opera Mobile10.1+
The root getter steps are to return this’s root.
In all current engines.
Firefox3.5+Safari3+Chrome1+ OperaYesEdge79+ Edge (Legacy)17+IENone Firefox for Android4+iOS Safari3+Chrome for Android18+Android WebView1+Samsung Internet1.0+Opera MobileYes
The referenceNode getter steps are to return this’s reference.
NodeIterator/pointerBeforeReferenceNode
In all current engines.
Firefox3.5+Safari3+Chrome1+ OperaYesEdge79+ Edge (Legacy)17+IENone Firefox for Android4+iOS Safari3+Chrome for Android18+Android WebView1+Samsung Internet1.0+Opera MobileYes