DOMTokenList.keys()
The keys()
method of the DOMTokenList
interface
returns an iterator allowing to go through all keys contained in this object.
The keys are unsigned integers.
Syntax
keys();
Parameters
None.
Return value
Returns an iterator.
Examples
In the following example we retrieve the list of classes set on a
<span>
element as a DOMTokenList
using
Element.classList
. We then retrieve an iterator containing the keys using keys()
,
then iterate through those keys using a for...of loop,
writing each one to the <span>
's Node.textContent
.
First, the HTML:
<span class="a b c"></span>
Now the JavaScript:
const span = document.querySelector("span");
const classes = span.classList;
const iterator = classes.keys();
for(let value of iterator) {
span.textContent += `(${value}) `;
}
The output looks like this:
Specifications
No specification found
No specification data found for api.DOMTokenList.keys
.
Check for problems with this page or contribute a missing spec_url
to mdn/browser-compat-data. Also make sure the specification is included in w3c/browser-specs.
Browser compatibility
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