Element: classList property - Web APIs | MDN (original) (raw)
Value
A DOMTokenList object representing the contents of the element's class attribute. If the class attribute is not set or empty, it returns an empty DOMTokenList, i.e., a DOMTokenList with the length property equal to 0.
Although the classList property itself is read-only in the sense that you can't replace the DOMTokenList object, you can still assign to the classList property directly, which is equivalent to assigning to its value property. You can also modify the DOMTokenList object using the add(), remove(), replace(), and toggle() methods.
Examples
const div = document.createElement("div");
div.classList = "foo"; // forwarded to classList.value
// our starting state: <div class="foo"></div>
console.log(div.outerHTML);
// use the classList API to remove and add classes
div.classList.remove("foo");
div.classList.add("another-class");
// <div class="another-class"></div>
console.log(div.outerHTML);
// if visible is set remove it, otherwise add it
div.classList.toggle("visible");
// add/remove visible, depending on test conditional, i less than 10
div.classList.toggle("visible", i < 10);
// false
console.log(div.classList.contains("foo"));
// add or remove multiple classes
div.classList.add("foo", "bar", "baz");
div.classList.remove("foo", "bar", "baz");
// add or remove multiple classes using spread syntax
const cls = ["foo", "bar"];
div.classList.add(...cls);
div.classList.remove(...cls);
// replace class "foo" with class "bar"
div.classList.replace("foo", "bar");
Specifications
| Specification |
|---|
| DOM # ref-for-dom-element-classlistâ‘ |