dom / latest / customstateset / add.html /

CustomStateSet.add()

The add method of the CustomStateSet interface adds an item to the CustomStateSet, after checking that the value is in the correct format.

Syntax

add(value)

Parameters

value

A string which must be a <dashed-ident>, with the form --mystate.

Return value

Undefined.

Exceptions

DOMException SyntaxError

Thrown if the string is not a <dashed-ident>.

Examples

The following function adds the state --checked to a CustomStateSet.

set checked(flag) {
  if (flag) {
    this._internals.states.add('--checked');
}

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
add
90
90
No
No
76
No
90
90
No
64
No
15.0

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https://developer.mozilla.org/en-US/docs/Web/API/CustomStateSet/add