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---
title: Reflect.has()
slug: Web/JavaScript/Reference/Global_Objects/Reflect/has
tags:
- ECMAScript 2015
- JavaScript
- Method
- Reference
- Reflect
translation_of: Web/JavaScript/Reference/Global_Objects/Reflect/has
---
<div>{{JSRef}}</div>
<p><code><strong>Reflect</strong></code><strong><code>.has()</code></strong> 정적 메서드는 <a href="/ko/docs/Web/JavaScript/Reference/Operators/in"><code>in</code> 연산자</a>의 함수판입니다.</p>
<div>{{EmbedInteractiveExample("pages/js/reflect-has.html")}}</div>
<h2 id="구문">구문</h2>
<pre class="syntaxbox">Reflect.has(<em>target</em>, <em>propertyKey</em>)
</pre>
<h3 id="매개변수">매개변수</h3>
<dl>
<dt><code>target</code></dt>
<dd>속성을 탐색할 객체.</dd>
<dt><code>propertyKey</code></dt>
<dd>탐색할 속성의 이름.</dd>
</dl>
<h3 id="반환_값">반환 값</h3>
<p>객체가 속성을 가지고 있는지 나타내는 {{jsxref("Boolean")}}.</p>
<h3 id="예외">예외</h3>
<p><code>target</code>이 {{jsxref("Object")}}가 아니면 {{jsxref("TypeError")}}.</p>
<h2 id="설명">설명</h2>
<p><code>Reflect.has()</code> 메서드는 객체에 속성이 존재하는지 판별할 수 있습니다. <a href="/ko/docs/Web/JavaScript/Reference/Operators/in"><code>in</code> 연산자</a>처럼 동작합니다.</p>
<h2 id="예제">예제</h2>
<h3 id="Reflect.has()_사용하기"><code>Reflect.has()</code> 사용하기</h3>
<pre class="brush: js">Reflect.has({x: 0}, 'x'); // true
Reflect.has({x: 0}, 'y'); // false
// 프로토타입 체인에 존재하는 속성도 true 반환
Reflect.has({x: 0}, 'toString');
// .has() 처리기 메서드를 가진 Proxy
obj = new Proxy({}, {
has(t, k) { return k.startsWith('door'); }
});
Reflect.has(obj, 'doorbell'); // true
Reflect.has(obj, 'dormitory'); // 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('ES2015', '#sec-reflect.has', 'Reflect.has')}}</td>
<td>{{Spec2('ES2015')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-reflect.has', 'Reflect.has')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="브라우저_호환성">브라우저 호환성</h2>
<p>{{Compat("javascript.builtins.Reflect.has")}}</p>
<h2 id="같이_보기">같이 보기</h2>
<ul>
<li>{{jsxref("Reflect")}}</li>
<li><a href="/ko/docs/Web/JavaScript/Reference/Operators/in"><code>in</code> 연산자</a></li>
</ul>
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