In this section, we will learn what the Set has() method is and how to use it in JavaScript.

What is JavaScript Set has() Method?

When we want to check whether a value is already in a `Set` object, we use the `has()` method.

JavaScript Set has() Method Syntax:

has(value)

has() Function Parameters:

The method takes one argument, and that is the target value we want to check a Set object for.

has() Function Return Value:

The return value of this method is a boolean.

If the target Set object has the argument value, then the result of this method is true.

Otherwise, the result will be false.

Example: using Set has() method in JavaScript

const collect = new Set();
collect.add("Jack");
collect.add("Jack");
collect.add("Omid");
collect.add("John");

if (collect.has("Jack")){
  console.log("The value 'Jack' is in this collection");
}
if (collect.has("Jason")){
  console.log("The value 'Jason' is in this collection");
}else{
  console.log("The value 'Jason' is not in this collection");
}

Output:

The value 'Jack' is in this collection

The value 'Jason' is not in this collection