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The ParentNode.firstElementChild
read-only property returns the object's first child Element
, or null
if there are no child elements.
This property was initially defined in the ElementTraversal
pure interface. As this interface contained two distinct set of properties, one aimed at Node
that have children, one at those that are children, they have been moved into two separate pure interfaces, ParentNode
and ChildNode
. In this case, firstElementChild
moved to ParentNode
. This is a fairly technical change that shouldn't affect compatibility.
Syntax
var childNode = elementNodeReference.firstElementChild;
Example
<p id="para-01"> <span>First span</span> </p> <script type="text/javascript"> var p01 = document.getElementById('para-01'); alert(p01.firstElementChild.nodeName) </script>
In this example, the alert shows 'span', which is the tag name of the first child node of the paragraph element.
Polyfill for Internet Explorer 8
This property is unsupported prior to IE9, so the following snippet can be used to add support to IE8:
// Source: https://github.com/Alhadis/Snippets/blob/master/js/polyfills/IE8-child-elements.js if(!("firstElementChild" in document.documentElement)){ Object.defineProperty(Element.prototype, "firstElementChild", { get: function(){ for(var nodes = this.children, n, i = 0, l = nodes.length; i < l; ++i) if(n = nodes[i], 1 === n.nodeType) return n; return null; } }); }
Specification
Specification | Status | Comment |
---|---|---|
DOM The definition of 'ParentNode.firstElementChild' in that specification. |
Living Standard | Splitted the ElementTraversal interface in ChildNode and ParentNode . This method is now defined on the latter.The Document and DocumentFragment implemented the new interfaces. |
Element Traversal Specification The definition of 'ElementTraversal.firstElementChild' in that specification. |
Recommendation | Added its initial definition to the ElementTraversal pure interface and use it on Element . |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support (on Element ) |
1.0 | 3.5 (1.9.1) | 9.0 | 10.0 | 4.0 |
Support on Document and DocumentFragment |
29.0 | 25.0 (25.0) | Not supported | 16.0 | Not supported |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support (on Element ) |
(Yes) | 1.0 (1.9.1) | (Yes) | (Yes) | (Yes) |
Support on Document and DocumentFragment |
(Yes) | 25.0 (25.0) | Not supported | 16.0 | Not supported |
See also
- The
ParentNode
andChildNode
pure interfaces.