In this article, we will cover how to check if a JavaScript object is of type Set. To achieve this, we will use the `instanceof` operator. We will check if the `prototype` property of the object `constructor` matches the `prototype` of `Set` object.
Check If A JavaScript Object Is Of Type Set
First, let’s create our `Set` object and initialize it with some values –
const set = new Set(["element1", "element2"]);
Now, let’s check if our `set` object is of type `Set` using the `instanceof` operator and print the result on the console. The `instanceof` operator should return `true` if our object matches the type `Set` and returns `false` otherwise.
console.log(set instanceof Set);

That’s it for checking for the type `Set`. We can just wrap the logic into a function so that we can dynamically check for the type of any object we need –
const isTypeSet = (object) => {
return object instanceof Set;
};
Let’s call the `isTypeSet` function and pass in our `set` object as an argument, and then check the output on the console.
console.log(isTypeSet(set));

As we can see, we got `true` as our `set` object matches the type `Set`.