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---
title: 'Array.prototype[@@iterator]()'
slug: Web/JavaScript/Reference/Global_Objects/Array/@@iterator
tags:
- Array
- ECMAScript 2015
- Iterator
- JavaScript
- Method
- Prototype
- Reference
translation_of: Web/JavaScript/Reference/Global_Objects/Array/@@iterator
---
<div>{{JSRef}}</div>
<p><code><strong>@@iterator</strong></code> 屬性的初始值與 {{jsxref("Array.prototype.values()", "values()")}} 屬性的初始值為相同的的函式物件。</p>
<h2 id="語法">語法</h2>
<pre class="syntaxbox"><code><var>arr</var>[Symbol.iterator]()</code></pre>
<h3 id="回傳值">回傳值</h3>
<p>陣列的<strong>迭代器(iterator)</strong>函式,預設與 {{jsxref("Array.prototype.values()", "values()")}} 函式相同。</p>
<h2 id="範例">範例</h2>
<h3 id="使用_for...of_迴圈進行迭代">使用 <code>for...of</code> 迴圈進行迭代</h3>
<pre class="brush: js">var arr = ['w', 'y', 'k', 'o', 'p'];
var eArr = arr[Symbol.iterator]();
// your browser must support for..of loop
// and let-scoped variables in for loops
for (let letter of eArr) {
console.log(letter);
}
</pre>
<h3 id="另一種迭代方式">另一種迭代方式</h3>
<pre class="brush: js">var arr = ['w', 'y', 'k', 'o', 'p'];
var eArr = arr[Symbol.iterator]();
console.log(eArr.next().value); // w
console.log(eArr.next().value); // y
console.log(eArr.next().value); // k
console.log(eArr.next().value); // o
console.log(eArr.next().value); // p
</pre>
<h2 id="規範">規範</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-array.prototype-@@iterator', 'Array.prototype[@@iterator]()')}}</td>
<td>{{Spec2('ES2015')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-array.prototype-@@iterator', 'Array.prototype[@@iterator]()')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="瀏覽器相容性">瀏覽器相容性</h2>
<div>
<p>{{Compat("javascript.builtins.Array.@@iterator")}}</p>
</div>
<h2 id="參見">參見</h2>
<ul>
<li>{{jsxref("Array.prototype.keys()")}}</li>
<li>{{jsxref("Array.prototype.entries()")}}</li>
<li>{{jsxref("Array.prototype.forEach()")}}</li>
<li>{{jsxref("Array.prototype.every()")}}</li>
<li>{{jsxref("Array.prototype.some()")}}</li>
<li>{{jsxref("Array.prototype.values()")}}</li>
</ul>
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