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The length read-only property of the DOMTokenList interface is an integer representing the number of objects stored in the object.

Syntax

tokenList.length;

Value

An integer.

Examples

In the following example we retrieve the list of classes set on a <span> element as a DOMTokenList using Element.classList, then write the length of the list to the <span>'s Node.textContent.

First, the HTML:

<span class="a b c"></span>

Now the JavaScript:

var span = document.querySelector("span");
var classes = span.classList;
var length = classes.length;

span.textContent = 'classList length = ' + length;

The output looks like this:

Specifications

Specification Status Comment
DOM
The definition of 'length' in that specification.
Living Standard Initial definition

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
lengthChrome Full support 1Edge Full support 12Firefox Full support 50IE ? Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesFirefox Android Full support 50Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yes

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

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このページの貢献者: mdnwebdocs-bot, fscholz, chrisdavidmills, jpmedley
最終更新者: mdnwebdocs-bot,