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---
title: Object.prototype.propertyIsEnumerable()
slug: Web/JavaScript/Reference/Global_Objects/Object/propertyIsEnumerable
tags:
- JavaScript
- Method
- Object
- Prototype
translation_of: Web/JavaScript/Reference/Global_Objects/Object/propertyIsEnumerable
---
<div>{{JSRef}}</div>
<p><code><strong>propertyIsEnumerable()</strong></code> 메서드는 특정 속성이 열거가능한지 여부를 나타내는 불리언 값을 반환합니다.</p>
<div>{{EmbedInteractiveExample("pages/js/object-prototype-propertyisenumerable.html")}}</div>
<h2 id="구문">구문</h2>
<pre class="syntaxbox"><code><var>obj</var>.propertyIsEnumerable(<var>prop</var>)</code></pre>
<h3 id="매개변수">매개변수</h3>
<dl>
<dt><code>prop</code></dt>
<dd>테스트 할 속성의 이름.</dd>
</dl>
<h3 id="반환_값">반환 값</h3>
<p>특정 속성이 열거가능한지 여부를 나타내는 {{jsxref("Boolean")}}.</p>
<h2 id="설명">설명</h2>
<p>모든 객체는 <code>propertyIsEnumerable</code> 메소드를 가지고 있습니다. 이 메소드는 프로토타입 체인을 통해 상속된 특성을 제외하고 개체에 지정된 속성을 {{jsxref("Statements/for...in", "for...in")}} 루프로 열거할 수 있는지 여부를 확인할 수 있습니다. 개체에 지정된 속성이 없으면 이 메소드는 <code>false</code>를 반환합니다.</p>
<h2 id="예제">예제</h2>
<h3 id="A_basic_use_of_propertyIsEnumerable">A basic use of <code>propertyIsEnumerable</code></h3>
<p>The following example shows the use of <code>propertyIsEnumerable</code> on objects and arrays:</p>
<pre class="brush: js">var o = {};
var a = [];
o.prop = 'is enumerable';
a[0] = 'is enumerable';
o.propertyIsEnumerable('prop'); // returns true
a.propertyIsEnumerable(0); // returns true
</pre>
<h3 id="User-defined_versus_built-in_objects">User-defined versus built-in objects</h3>
<p>The following example demonstrates the enumerability of user-defined versus built-in properties:</p>
<pre class="brush: js">var a = ['is enumerable'];
a.propertyIsEnumerable(0); // returns true
a.propertyIsEnumerable('length'); // returns false
Math.propertyIsEnumerable('random'); // returns false
this.propertyIsEnumerable('Math'); // returns false
</pre>
<h3 id="Direct_versus_inherited_properties">Direct versus inherited properties</h3>
<pre class="brush: js">var a = [];
a.propertyIsEnumerable('constructor'); // returns false
function firstConstructor() {
this.property = 'is not enumerable';
}
firstConstructor.prototype.firstMethod = function() {};
function secondConstructor() {
this.method = function method() { return 'is enumerable'; };
}
secondConstructor.prototype = new firstConstructor;
secondConstructor.prototype.constructor = secondConstructor;
var o = new secondConstructor();
o.arbitraryProperty = 'is enumerable';
o.propertyIsEnumerable('arbitraryProperty'); // returns true
o.propertyIsEnumerable('method'); // returns true
o.propertyIsEnumerable('property'); // returns false
o.property = 'is enumerable';
o.propertyIsEnumerable('property'); // returns true
// These return false as they are on the prototype which
// propertyIsEnumerable does not consider (even though the last two
// are iteratable with for-in)
o.propertyIsEnumerable('prototype'); // returns false (as of JS 1.8.1/FF3.6)
o.propertyIsEnumerable('constructor'); // returns false
o.propertyIsEnumerable('firstMethod'); // returns false
</pre>
<h2 id="명세">명세</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('ES3')}}</td>
<td>{{Spec2('ES3')}}</td>
<td>Initial definition</td>
</tr>
<tr>
<td>{{SpecName('ES5.1', '#sec-15.2.4.7', 'Object.prototype.propertyIsEnumerable')}}</td>
<td>{{Spec2('ES5.1')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('ES6', '#sec-object.prototype.propertyisenumerable', 'Object.prototype.propertyIsEnumerable')}}</td>
<td>{{Spec2('ES6')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-object.prototype.propertyisenumerable', 'Object.prototype.propertyIsEnumerable')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td></td>
</tr>
</tbody>
</table>
<h2 id="브라우저_호환성">브라우저 호환성</h2>
<p>{{Compat("javascript.builtins.Object.propertyIsEnumerable")}}</p>
<h2 id="같이_보기">같이 보기</h2>
<ul>
<li><a href="/en-US/docs/Enumerability_and_ownership_of_properties">Enumerability and ownership of properties</a></li>
<li>{{jsxref("Statements/for...in", "for...in")}}</li>
<li>{{jsxref("Object.keys()")}}</li>
<li>{{jsxref("Object.defineProperty()")}}</li>
</ul>
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