DOMTokenList.contains()

The contains() method of the DOMTokenList interface returns a Boolean โ€” 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 existance of in the list.

Return value

A Boolean โ€” true if the underlying list contains the given 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 existance 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:

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

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