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---
title: DataView.prototype.getUint8()
slug: Web/JavaScript/Reference/Global_Objects/DataView/getUint8
tags:
- 类型化
- 类型化数组
translation_of: Web/JavaScript/Reference/Global_Objects/DataView/getUint8
---
<div>{{JSRef}}</div>
<p><strong><code>getUint8()</code></strong><code>方法</code><code>从</code>{{jsxref("DataView")}}相对于起始位置偏移 n 个字节处开始，获取一个无符号的8-bit整数(一个字节).</p>
<div>{{EmbedInteractiveExample("pages/js/dataview-getuint8.html")}}</div>
<h2 id="语法">语法</h2>
<pre class="syntaxbox"><var>dataview</var>.getUint8(byteOffset)</pre>
<h2 id="参数">参数</h2>
<dl>
<dt>byteOffset</dt>
<dd>偏移量, 单位为字节, 从头开始计算.</dd>
</dl>
<h3 id="抛出错误">抛出错误</h3>
<dl>
<dt>{{jsxref("RangeError")}}</dt>
<dd>如果byteOffset超出了视图能储存的值，就会抛出错误.</dd>
</dl>
<h2 id="描述">描述</h2>
<dl>
<dd> 没有对齐约束; 多字节值可以从任何偏移量获取.</dd>
</dl>
<h2 id="例子">例子</h2>
<pre class="brush:js">var buffer = new ArrayBuffer(8);
var dataview = new DataView(buffer);
dataview.getUint8(1); // 0
</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">说明</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Superseded by ECMAScript 6.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-dataview.prototype.getuint8', 'DataView.prototype.getUint8')}}</td>
<td>{{Spec2('ES6')}}</td>
<td>Initial definition in an ECMA standard.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-dataview.prototype.getuint8', 'DataView.prototype.getUint8')}}</td>
<td>{{Spec2('ESDraft')}}</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.getUint8")}}</p>
<h2 id="相关内容">相关内容</h2>
<ul>
<li>{{jsxref("DataView")}}</li>
<li>{{jsxref("ArrayBuffer")}}</li>
</ul>
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