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web api instance method

CustomStateSet: add() method

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The add method of the CustomStateSet interface adds value representing a custom state to the CustomStateSet.

Custom elements with a specific state can be selected using the :state() pseudo-class, specifying the desired state as an argument.

Syntax

add(value)

Parameters

  • value
    • : A string that represents the custom state.

Return value

Undefined.

Examples

The following function adds the state checked to a CustomStateSet.

class MyCustomElement extends HTMLElement {
  set checked(flag) {
    if (flag) {
      this._internals.states.add("checked");
    }
  }
}

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.