---
title: getBigInt64()
slug: Web/JavaScript/Reference/Global_Objects/DataView/getBigInt64
tags:
  - DataView
  - JavaScript
  - Prototype
  - getBigInt64()
  - 大整型
translation_of: Web/JavaScript/Reference/Global_Objects/DataView/getBigInt64
---
<div>{{JSRef}}</div>

<div></div>

<p><strong><code>getBigInt64()</code></strong> 方法从 {{jsxref("DataView")}}开始获取一个指定偏移量的有符号64位整数 (long long) 。</p>

<div>{{EmbedInteractiveExample("pages/js/dataview-getbigint64.html")}}</div>



<h2 id="语法">语法</h2>

<pre class="syntaxbox"><var>dataview</var>.getBigInt64(byteOffset [, littleEndian])</pre>

<h3 id="参数">参数</h3>

<dl>
 <dt>byteOffset</dt>
 <dd>偏移量，以字节为单位。指明视图开始读取数据的偏移量。</dd>
 <dt>littleEndian</dt>
 <dd>{{optional_inline}} 指明该64位整型数值的存储方式（ {{Glossary("Endianness", "大小端模式")}}） 。 如果为 <code>false</code> 或 <code>undefined</code>, 则按大端方式读取数据。</dd>
</dl>

<h3 id="返回值">返回值</h3>

<p>一个 {{jsxref("BigInt")}}.</p>

<h3 id="异常抛出">异常抛出</h3>

<dl>
 <dt>{{jsxref("RangeError")}}</dt>
 <dd>如果 <code>byteOffset</code> 设置的偏移量超出了视图的范围，则抛出该异常。</dd>
</dl>

<h2 id="简介">简介</h2>

<ul>
 <li>没有对齐约束;</li>
 <li>可以从任何偏移量获取多字节值。</li>
</ul>

<h2 id="例子">例子</h2>

<h3 id="使用_getBigInt64_方法">使用 <code>getBigInt64</code> 方法</h3>

<pre class="brush:js">var buffer = new ArrayBuffer(8);
var dataview = new DataView(buffer);
dataview.getBigInt64(0); // 0n
</pre>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">规范版本</th>
   <th scope="col">规范状态</th>
   <th scope="col">注解      </th>
  </tr>
  <tr>
   <td><a href="https://tc39.github.io/proposal-bigint/#sec-dataview.prototype.getbigint64">DataView.prototype.getBigInt64 proposal</a></td>
   <td></td>
   <td></td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>



<p>{{Compat("javascript.builtins.DataView.getBigInt64")}}</p>

<h2 id="另请参阅">另请参阅</h2>

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