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
| Specification | Status | Comment |
|---|---|---|
| DOM The definition of 'TreeWalker.firstChild' in that specification. |
Living Standard | No change from Document Object Model (DOM) Level 2 Traversal and Range Specification |
| Document Object Model (DOM) Level 2 Traversal and Range Specification The definition of 'TreeWalker.firstChild' in that specification. |
Recommendation | Initial definition. |
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
- The
TreeWalkerinterface it belongs to.