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TreeWalker: firstChild() method

files/en-us/web/api/treewalker/firstchild/index.md

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{{ APIRef("DOM") }}

The TreeWalker.firstChild() method moves the current {{domxref("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-nolint
firstChild()

Parameters

None.

Return value

A {{domxref("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

{{Specifications}}

Browser compatibility

{{Compat}}

See also

  • The {{domxref("TreeWalker")}} interface it belongs to.