JavaScript Set has() Method

The Set.has() method in JavaScript is used to check whether an element with a specified value exists in a Set or not. It returns a boolean value indicating the presence or absence of an element with a specified value in a Set.

Syntax:

mySet.has(value);

Parameters:

• value: It is the value of the element that has to be checked if it exists in the Set.

Example 1: In this example, we have used sethas() method.

Javascript

// Create a new set using Set() constructor
let myset = new Set();

// Append new elements to the
// set using add() method
myset.add(23);
myset.add(12);

// As 23 exists 23, it will return true
console.log(myset.has(23));

Output

true

Example 2: In this example, we have used sethas() method.

Javascript

// Create a new set using Set() constructor
let myset = new Set();

// Append new elements to the
// set using add() method
myset.add("Chicago");
myset.add("California");
myset.add("London");

// As London exists in the set,
// it will return true
console.log(myset.has("London"));

// As Manchester does not exist in the
// set, it will return false
console.log(myset.has("Manchester"));

Output

true
false

We have a complete list of Javascript Set methods, to check those please go through this Sets in JavaScript article.

We have a Cheat Sheet on Javascript where we covered all the important topics of Javascript to check those please go through Javascript Cheat Sheet-A Basic guide to JavaScript.