Node.rootNode
This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The Node.rootNode
read-only property returns a Node
object representing the topmost node in the tree, or the current node if it's the topmost node in the tree. This is found by walking backward along Node.parentNode
until the top is reached.
For compatibility reason, this property will be renamed in the near future and no browser plans to ship it under this name.
Syntax
<var>rootNode</var> = node.rootNode;
Example
This example constructs a simple DOM tree of elements, then displays information about a specific node followed by the base URI of its root node.
HTML
<div id="outer"> <div id="inner"> <a id="button" href="go.html"> Hello </a> <p><em id="me">It's me.</em></p> <p>I was wondering if after all these years, you still code in C...</p> </div> </div> <pre id="output"> </pre>
JavaScript
let output = document.getElementById("output"); let me = document.getElementById("me"); output.innerHTML += "Element with id 'me': " + me.outerHTML + "<br>"; output.innerHTML += "Root node's base URI: " + me.rootNode.baseURI;
p { margin: 0px; } #output { width: 640px; border: 2px solid black; border-radius: 5px; padding: 10px; margin-top: 20px; display: block; overflow: scroll; }
Notes
Gecko-based browsers insert text nodes into a document to represent whitespace in the source markup.
Therefore a node obtained, for example, using Node.firstChild
or Node.previousSibling
may refer to a
whitespace text node rather than the actual element the author intended to get.
See Whitespace in the DOM and W3C DOM 3 FAQ: Why are some Text nodes empty? for more information.
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | ? | 48 (48)[1] | ? | ? | ? |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | ? | 48.0 (48)[1] | ? | ? | ? |
[1] Not activated by default; it is behind the pref dom.node.rootNode.enabled
and you need to set it to true
to activate it.
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'Node.rootNode' in that specification. |
Living Standard | Initial definition |
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/node/rootnode