---
title: ArrayBuffer.prototype.byteLength
slug: Web/JavaScript/Reference/Global_Objects/ArrayBuffer/byteLength
translation_of: Web/JavaScript/Reference/Global_Objects/ArrayBuffer/byteLength
---
<div>{{JSRef}}</div>

<p><code><strong>byteLength</strong>访问器属性</code>表示一个{{jsxref("ArrayBuffer")}} 对象的字节长度。</p>

<div>{{EmbedInteractiveExample("pages/js/arraybuffer-bytelength.html")}}</div>



<h2 id="语法">语法</h2>

<pre class="syntaxbox"><var>arr</var>aybuffer.byteLength</pre>

<h2 id="描述">描述</h2>

<p>byteLength属性是一个访问器属性，它的set访问器函数是undefined，这意味着你只能读这个属性。 该值在数组创建时确定，并且不可变更。如果这个<code>ArrayBuffer</code> 被移除，则此属性返回0。</p>

<p> </p>

<h2 id="示例">示例</h2>

<pre class="brush:js">var buffer = new ArrayBuffer(8);
buffer.byteLength; // 8
</pre>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">规范</th>
   <th scope="col">状态</th>
   <th scope="col">备注</th>
  </tr>
  <tr>
   <td>{{SpecName('Typed Array')}}</td>
   <td>{{Spec2('Typed Array')}}</td>
   <td>Superseded by ECMAScript 6.</td>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#sec-get-arraybuffer.prototype.bytelength', 'ArrayBuffer.prototype.byteLength')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>Initial definition in an ECMA standard.</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>



<p>{{Compat("javascript.builtins.ArrayBuffer.byteLength")}}</p>

<h2 id="相关链接">相关链接</h2>

<ul>
 <li>{{jsxref("ArrayBuffer")}}</li>
</ul>