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目录

HTML DOM Element firstChild

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Example

Return the HTML content of the first child node of an <ul> element:

document.getElementById("myList").firstChild.innerHTML;
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Get the text of the first child node of a <select> element:

let text = document.getElementById("mySelect").firstChild.text;
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More examples below.

Description

The firstChild property returns the first child node of a node.

The firstChild property returns a node object.

The firstChild property is read-only.

The firstChild property is the same as childNodes[0].

Important!

firstChild returns the first child node: An element node, a text node, or a comment node.

Whitespace between elements are also text nodes.

Alternative:

The firstElementChild Property

The firstElementChild property returns the first child element (ignores text and comment nodes).

See Also:

The childNodes Property

The lastChild Property

The nextSibling Property

The previousSibling Property

Node Properties

The parentNode Property

The nodeName Property

The nodeType Property

The nodeValue Property

Nodes vs Elements

In the HTML DOM terminology:

Nodes are all nodes (element nodes, text nodes, and comment nodes).

Whitespace between elements are also text nodes.

Elements are only element nodes.

childNodes vs children

childNodes returns child nodes (element nodes, text nodes, and comment nodes).

children returns child elements (not text and comment nodes).

firstChild vs firstElementChild

firstChild returns the first child node (an element node, a text node or a comment node). Whitespace between elements are also text nodes.

firstElementChild returns the first child element (not text and comment nodes).

lastChild vs lastElementChild

lastChild returns the last child node (an element node, a text node or a comment node). Whitespace between elements are also text nodes.

lastElementChild returns the last child element (not text and comment nodes).

Syntax

element.firstChild
node.firstChild

Return Value

Type Description
Node The first child of a node.
nullif no child exists.

More Examples

This example demonstrates how whitespace may interfere.

Try to get the node name of the first child node of "myDIV":

<div id="myDIV">
  <p>Looks like first child</p>
  <p>Looks like last Child</p>
</div>

<script>
let text = document.getElementById("myDIV").firstChild.nodeName;
</script>
Try it Yourself »

However, if you remove the whitespace from the source, there are no #text nodes in "myDIV":

<div id="myDIV"><p>First child</p><p>Last Child</p></div>

<script>
let text = document.getElementById("myDIV").firstChild.nodeName;
</script>
Try it Yourself »

Browser Support

element.firstChild is a DOM Level 1 (1998) feature.

It is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes 9-11
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