---
title: Set.prototype.has()
slug: Web/JavaScript/Reference/Global_Objects/Set/has
translation_of: Web/JavaScript/Reference/Global_Objects/Set/has
---
<div>{{JSRef}}</div>

<p>Метод  <code><strong>has()</strong></code> возвращает логическое значение, показывающее, существует ли элемент с указанным значением в объекте  <code>Set</code> или нет.</p>

<div>{{EmbedInteractiveExample("pages/js/set-prototype-has.html")}}</div>



<h2 id="Syntax">Syntax</h2>

<pre class="syntaxbox"><code><em>mySet</em>.has(value);</code></pre>

<h3 id="Parameters">Parameters</h3>

<dl>
 <dt>value</dt>
 <dd>Required. The value to test for presence in the <code>Set</code> object.</dd>
</dl>

<h3 id="Return_value">Return value</h3>

<dl>
 <dt>Boolean</dt>
 <dd>
 <p>Returns <code>true</code> if an element with the specified value exists in the <code>Set</code> object; otherwise <code>false</code>.</p>

 <div class="note">
 <p><strong>Note:</strong> Technically speaking, <code>has()</code> uses the <code><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness#Same-value-zero_equality">sameValueZero</a></code> algorithm to determine whether the given element is found.</p>
 </div>
 </dd>
</dl>

<h2 id="Examples">Examples</h2>

<h3 id="Using_the_has_method">Using the <code>has</code> method</h3>

<pre class="brush: js">var mySet = new Set();
mySet.add('foo');

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

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

set1.has(obj1);        // returns true
set1.has({'key1': 1}); // returns false because they are different object references
set1.add({'key1': 1}); // now set1 contains 2 entries
</pre>

<h2 id="Specifications">Specifications</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('ES2015', '#sec-set.prototype.has', 'Set.prototype.has')}}</td>
   <td>{{Spec2('ES2015')}}</td>
   <td>Initial definition.</td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-set.prototype.has', 'Set.prototype.has')}}</td>
   <td>{{Spec2('ESDraft')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>



<p>{{Compat("javascript.builtins.Set.has")}}</p>

<h2 id="See_also">See also</h2>

<ul>
 <li>{{jsxref("Set")}}</li>
 <li>{{jsxref("Set.prototype.add()")}}</li>
 <li>{{jsxref("Set.prototype.delete()")}}</li>
</ul>