This feature is not Baseline because it does not work in some of the most widely-used browsers.
Note: This feature is available in Web Workers.
The isHTML() method of the TrustedTypePolicyFactory interface returns true if it is passed a valid TrustedHTML object.
Note: The purpose of the functions isHTML(), isScript(), and isScriptURL() is to check if the object is a valid TrustedType object, created by a configured policy.
isHTML(value)
valueA TrustedHTML object.
A boolean that is true if the object is a valid TrustedHTML object.
In the below example the constant html was created by a policy, and therefore isHTML() returns true. The second example is an attempt to fake an object, and the third is a string. Both of these will return false when passed to isHTML().
const html = policy.createHTML("<div>");
console.log(trustedTypes.isHTML(html)); // true;
const fake = Object.create(TrustedHTML.prototype);
console.log(trustedTypes.isHTML(fake)); // false
console.log(trustedTypes.isHTML("<div>plain string</div>")); // false
| Specification |
|---|
| Trusted Types> # dom-trustedtypepolicyfactory-ishtml> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
isHTML |
83 | 83 | No | 69 | 26 | 83 | No | 59 | 26 | 13.0 | 83 | 26 |
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https://developer.mozilla.org/en-US/docs/Web/API/TrustedTypePolicyFactory/isHTML