W3cubDocs

/Web APIs

DOMTokenList: supports() method

The supports() method of the DOMTokenList interface returns true if a given token is in the associated attribute's supported tokens. This method is intended to support feature detection.

Syntax

js

supports(token)

Parameters

token

A string containing the token to query for.

Returns

A boolean value indicating whether the token was found.

Example

js

const iframe = document.getElementById("display");

if (iframe.sandbox.supports("an-upcoming-feature")) {
  // support code for mystery future feature
} else {
  // fallback code
}

if (iframe.sandbox.supports("allow-scripts")) {
  // instruct frame to run JavaScript
  //
  // (NOTE: This feature is well-supported; this is just an example!)
  //
}

Specifications

Specification
DOM Standard
# ref-for-dom-domtokenlist-supports①

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
supports 49 17 49 No 36 10.1 49 49 49 36 10.3 5.0

© 2005–2023 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/DOMTokenList/supports