DOMTokenList.contains()
The contains()
method of the DOMTokenList
interface returns a Boolean
— true
if the underlying list
contains the given token
, otherwise false
.
Syntax
tokenList.contains(token);
Parameters
token
- A
DOMString
representing the token you want to check for the existence of in the list.
Return value
A Boolean
, which is true
if the calling list contains
token
, otherwise false
.
Examples
In the following example we retrieve the list of classes set on a
<span>
element as a DOMTokenList
using
Element.classList
. We then test for the existence of "c"
in
the list, and write the result into the <span>
's
Node.textContent
.
First, the HTML:
<span class="a b c"></span>
Now the JavaScript:
let span = document.querySelector("span");
let classes = span.classList;
let result = classes.contains("c");
if (result) {
span.textContent = "The classList contains 'c'";
} else {
span.textContent = "The classList does not contain 'c'";
}
The output looks like this:
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'contains()' in that specification. |
Living Standard | Initial definition |
Browser compatibility
BCD tables only load in the browser