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

Syntax

mySet.has(value);

Parameters

value
Required. The value to test for presence in the Set object.

Return value

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

Examples

Using the has method

var mySet = new Set();
mySet.add('foo');

mySet.has('foo');  // returns true
mySet.has('bar');  // returns false

Specifications

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Set.prototype.has' in that specification.
Standard Initial definition.
ECMAScript Latest Draft (ECMA-262)
The definition of 'Set.prototype.has' in that specification.
Draft  

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 38 (Yes) 13.0 (13.0) 11 25 7.1
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 38 (Yes) 13.0 (13.0) No support No support 8

See also

Document Tags and Contributors

 Contributors to this page: jameshkramer, nmve, kdex, fscholz, realityking
 Last updated by: jameshkramer,