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DOMTokenList: supports() method - Web APIs | MDN
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DOMTokenList: supports() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.
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.
Return value
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 # ref-for-dom-domtokenlist-supports① |
Browser compatibility
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