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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.
Obsolete Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
firstChildChrome Full support 1Edge Full support 12Firefox Full support 4IE Full support 9Opera Full support 9Safari Full support 3WebView Android Full support 3Chrome Android Full support YesFirefox Android Full support 4Opera Android Full support 10.1Safari iOS Full support 3Samsung Internet Android ?

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also

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