Set.prototype.has()

The has() method returns a boolean indicating whether an element with the specified value exists in a Set object or not.

Try it

Syntax

js

has(value)

Parameters

value

The value to test for presence in the Set object.

Return value

Returns true if an element with the specified value exists in the Set object; otherwise false.

Examples

Using the has() method

js

const mySet = new Set();
mySet.add("foo");

console.log(mySet.has("foo")); // true
console.log(mySet.has("bar")); // false

const set1 = new Set();
const obj1 = { key1: 1 };
set1.add(obj1);

console.log(set1.has(obj1)); // true
console.log(set1.has({ key1: 1 })); // false, because they are different object references
console.log(set1.add({ key1: 1 })); // now set1 contains 2 entries

Specifications

Specification
ECMAScript Language Specification
# sec-set.prototype.has

Browser compatibility

BCD tables only load in the browser

See also