The entries() method of the DOMTokenList interface returns an iterator allowing you to go through all key/value pairs contained in this object. The values are Arrays which have [key, value] pairs, each representing a single token.
entries()None.
Returns an iterator.
In the following example we retrieve the list of classes set on a <span> element as a DOMTokenList using Element.classList. We when retrieve an iterator containing the key/value pairs using entries(), then iterate through each one using a for...of loop, writing them 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.entries();
for (const value of iterator) {
span.textContent += `(${value})`;
}The output looks like this: