TrustedTypePolicyFactory: isHTML() method

Available in 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.

Syntax

isHTML(value)

Parameters

• value
  • : A TrustedHTML object.

Return value

A Boolean that is true if the object is a valid TrustedHTML object.

Examples

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

Specifications

Browser compatibility