Element: className property
The className
property of the
Element
interface gets and sets the value of the class
attribute
of the specified element.
Value
A string variable representing the class or space-separated classes of the current element.
Examples
const el = document.getElementById("item");
el.className = el.className === "active" ? "inactive" : "active";
Notes
The name className
is used for this property instead of class
because of conflicts with the "class" keyword in many languages which are used to
manipulate the DOM.
className
can also be an instance of SVGAnimatedString
if
the element
is an SVGElement
. It is easier to get/set the
class
attribute of an element using Element.getAttribute
and
Element.setAttribute
if you are dealing with SVG elements. However, take
into account that Element.getAttribute
returns
null
instead of ""
if the element
has an empty class
attribute.
elm.setAttribute("class", "my-class");
const myClass = elm.getAttribute("class");
Note: class
is the name of an HTML Attribute, while
className
is the name of a DOM Property.
Specifications
Specification |
---|
DOM Standard # ref-for-dom-element-classname① |
Browser compatibility
BCD tables only load in the browser