files/zh-cn/web/api/htmlcanvaselement/height/index.html


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---
title: HTMLCanvasElement.height
slug: Web/API/HTMLCanvasElement/height
translation_of: Web/API/HTMLCanvasElement/height
---
<div>
<div>
<div>{{APIRef("Canvas API")}}</div>
</div>
</div>

<p><strong><code><span>HTMLCanvasElement.height</span></code></strong> 属性是一个正<code>整数</code> ，使用了{{HTMLElement("canvas")}} 元素的HTML 属性{{htmlattrxref("height", "canvas")}}来反映该元素高度的 CSS 像素值。当该属性没有被定义，或被定义为一个无效值（如负值）时， 将使用<code>150</code>作为它的默认值。</p>

<p>控制canvas元素大小的属性有两个，这是其中一个，还有一个是{{domxref("HTMLCanvasElement.width")}}。</p>

<h2 id="Syntax" name="Syntax">语法</h2>

<pre class="syntaxbox"><var>var <em>pxl</em> = <em>canvas</em></var>.height;
<em>canvas</em>.height = <em>pxl</em>;
</pre>

<h2 id="示例">示例</h2>

<p>给出这样一个{{HTMLElement("canvas")}} 元素：</p>

<pre class="brush: html">&lt;canvas id="canvas" width="300" height="300"&gt;&lt;/canvas&gt;
</pre>

<p>可以通过以下代码获得这个canvas元素的高度：</p>

<pre class="brush: js">var canvas = document.getElementById('canvas');
console.log(canvas.height); // 300
</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('HTML WHATWG', "scripting.html#attr-canvas-height", "HTMLCanvasElement.height")}}</td>
   <td>{{Spec2('HTML WHATWG')}}</td>
   <td>No change since the latest snapshot, {{SpecName('HTML5 W3C')}}</td>
  </tr>
  <tr>
   <td>{{SpecName('HTML5.1', "scripting-1.html#attr-canvas-height", "HTMLCanvasElement.height")}}</td>
   <td>{{Spec2('HTML5.1')}}</td>
   <td> </td>
  </tr>
  <tr>
   <td>{{SpecName('HTML5 W3C', "scripting-1.html#attr-canvas-height", "HTMLCanvasElement.height")}}</td>
   <td>{{Spec2('HTML5 W3C')}}</td>
   <td>Snapshot of the {{SpecName('HTML WHATWG')}} containing the initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

<p>{{ CompatibilityTable() }}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Chrome</th>
   <th>Edge</th>
   <th>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatChrome(4) }}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{ CompatGeckoDesktop("1.9.2") }}</td>
   <td>{{ CompatIE(9) }}</td>
   <td>{{ CompatOpera(9) }}</td>
   <td>{{ CompatSafari(3.1) }}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Android</th>
   <th>Chrome for Android</th>
   <th>Edge</th>
   <th>Firefox Mobile (Gecko)</th>
   <th>IE Mobile</th>
   <th>Opera Mobile</th>
   <th>Safari Mobile</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{ CompatGeckoMobile("1.9.2") }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
  </tr>
 </tbody>
</table>
</div>

<h2 id="See_Also" name="See_Also">其他</h2>

<ul>
 <li>定义的接口, {{domxref("HTMLCanvasElement")}}.</li>
 <li>另一个控制canvas大小的属性, {{domxref("HTMLCanvasElement.width")}}.</li>
</ul>