ElementInternals: validity property

The validity read-only property of the ElementInternals interface returns a ValidityState object which represents the different validity states the element can be in, with respect to constraint validation.

Value

A ValidityState object.

Exceptions

NotSupportedError DOMException

Thrown if the element does not have its formAssociated property set to true.

Examples

The following example shows a custom checkbox component with formAssociated set to true, the value of validity.valid is logged to the console.

class CustomCheckbox extends HTMLElement {
 static formAssociated = true;
 constructor() {
 super();
 this.internals_ = this.attachInternals();
 }
 // ...
}
window.customElements.define("custom-checkbox", CustomCheckbox);
let element = document.getElementById("custom-checkbox");
console.log(element.internals_.validity.valid);

Specifications

Browser compatibility