TreeWalker: firstChild() method
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The TreeWalker.firstChild()
method moves the current
Node
to the first visible child of the current node, and returns
the found child. If no such child exists, it returns null
and the current node is not changed.
Syntax
js
firstChild()
Parameters
None.
Return value
A Node
object or null
.
Examples
js
const treeWalker = document.createTreeWalker(
document.body,
NodeFilter.SHOW_ELEMENT,
{
acceptNode(node) {
return NodeFilter.FILTER_ACCEPT;
},
},
false,
);
const node = treeWalker.firstChild(); // returns the first child of the root element, or null if none
Specifications
Specification |
---|
DOM Standard # dom-treewalker-firstchild |
Browser compatibility
BCD tables only load in the browser
See also
- The
TreeWalker
interface it belongs to.