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---
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>
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