TreeWalker: firstChild() method
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
| desktop | mobile | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
firstChild | |||||||||||
See also
- The
TreeWalkerinterface it belongs to.