Web/API/DocumentFragment/querySelector

The DocumentFragment.querySelector() method returns the first element, or null if no matches are found, within the DocumentFragment (using depth-first pre-order traversal of the document's nodes) that matches the specified group of selectors.

If the selector matches an ID and this ID is erroneously used several times in the document, it returns the first matching element.

If the selectors specified in parameter are invalid a DOMException with a SYNTAX_ERR value is raised.

Syntax

element = documentfragment.querySelector(selectors);

Parameters

selectors: Is a DOMString containing one or more CSS selectors separated by commas.

Examples

Basic example

In this basic example, the first element in the DocumentFragment with the class "myclass" is returned:

var el = documentfragment.querySelector(".myclass");

CSS syntax and the method's argument

The string argument pass to querySelector must follow the CSS syntax. To match ID or selectors that do not follow the CSS syntax (by using semicolon or space inappropriately for example), it's mandatory to escape the wrong character with a double back slash:

<div id="foo\bar"></div>
<div id="foo:bar"></div>

<script>
document.querySelector('#foo\bar')    // Does not match anything
document.querySelector('#foo\\\\bar') // Match the first div
document.querySelector('#foo:bar')     // Does not match anything
document.querySelector('#foo\\:bar')   // Match the second div
</script>

Specifications

Specification	Status	Comment
Selectors API Level 2The definition of 'DocumentFragment.querySelector' in that specification.	Obsolete	No change from Selectors API Level 1
Selectors API Level 1The definition of 'DocumentFragment.querySelector' in that specification.	Obsolete	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`querySelector`	Chrome Full support 1	Edge Full support 12	Firefox Full support 3.5	IE Full support 9	Opera Full support 10	Safari Full support 3.2	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 3.2	Samsung Internet Android Full support Yes

Legend

Full support: Full support