Since March 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The willValidate read-only property of the ElementInternals interface returns true if the element is a submittable element that is a candidate for constraint validation.
Elements that are barred from being candidates for constraint validation include those that have the attributes: disabled, hidden or readonly, input elements of type=button or type=reset, or any element that is a <datalist> element or has a <datalist> element ancestor.
true if the element is a candidate for constraint validation, otherwise false.
NotSupportedError DOMException
Thrown if the element does not have its formAssociated property set to true.
The following example shows a custom checkbox component with formAssociated set to true, the value of willValidate 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_.willValidate); // true
| Specification |
|---|
| HTML> # dom-elementinternals-willvalidate> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
willValidate |
77 | 79 | 98 | 64 | 16.4 | 77 | 98 | 55 | 16.4 | 12.0 | 77 | 16.4 |
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https://developer.mozilla.org/en-US/docs/Web/API/ElementInternals/willValidate