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/DOM

TreeWalker.firstChild

The TreeWalker.firstChild() method 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, returns null and the current node is not changed.

Syntax

node = treeWalker.firstChild;

Example

var treeWalker = document.createTreeWalker(
    document.body,
    NodeFilter.SHOW_ELEMENT,
    { acceptNode: function(node) { return NodeFilter.FILTER_ACCEPT; } },
    false
);
var node = treeWalker.firstChild(); // returns the first child of the root element, or null if none

Specifications

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 (Yes) 2.0 (1.8.1) 9.0 9.0 3.0
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) 1.0 (1.8.1) (Yes) 9.0 3.0

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/TreeWalker/firstChild