This feature is well established and works across many devices and browser versions. It’s been available across browsers since August 2016.
The checkValidity() method of the HTMLOutputElement interface checks if the element is valid, but always returns true because <output> elements are never candidates for constraint validation.
checkValidity()
None.
A boolean value, true.
In the following example, calling checkValidity() returns true.
const element = document.getElementById("myOutput");
console.log(element.checkValidity());
| Specification |
|---|
| HTML> # dom-cva-checkvalidity-dev> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
checkValidity |
9 | 14 | 4 | ≤12.1 | 5.1 | 18 | 4 | ≤12.1 | 5 | 1.0 | 3 | 5 |
HTMLOutputElement.reportValidity()<output><form>
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https://developer.mozilla.org/en-US/docs/Web/API/HTMLOutputElement/checkValidity