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---
title: HTMLElement.focus()
slug: Web/API/HTMLOrForeignElement/focus
tags:
- API
- 参考
- 方法
- 焦点
translation_of: Web/API/HTMLOrForeignElement/focus
original_slug: Web/API/HTMLElement/focus
---
<div>{{ APIRef("HTML DOM") }}</div>
<p><span class="seoSummary"><strong><code>HTMLElement.focus()</code></strong> 方法用于设置焦点，如果被指定的元素可以获取到焦点，焦点就会被设置到该元素上。得到焦点的元素会作为键盘导航时的当前元素/基准元素，也会接收到相应的键盘事件等事件。</span></p>
<h2 id="语法">语法</h2>
<pre class="syntaxbox"><var>element</var>.focus(<var>options</var>); // Object parameter</pre>
<h3 id="参数">参数</h3>
<dl>
<dt><code>options</code> {{optional_inline}}</dt>
<dd>An optional object providing options to control aspects of the focusing process. This object may contain the following property:</dd>
<dd>
<dl>
<dt><code>preventScroll</code> {{optional_inline}}</dt>
<dd>A Boolean value indicating whether or not the browser should scroll the document to bring the newly-focused element into view. A value of <code>false</code> for <code>preventScroll</code> (the default) means that the browser will scroll the element into view after focusing it. If <code>preventScroll</code> is set to <code>true</code>, no scrolling will occur.</dd>
</dl>
</dd>
</dl>
<h2 id="示例">示例</h2>
<h3 id="将焦点设置到文本框上">将焦点设置到文本框上</h3>
<h4 id="JavaScript">JavaScript</h4>
<pre class="brush: js">focusMethod = function getFocus() {
document.getElementById("myTextField").focus();
}</pre>
<h4 id="HTML">HTML</h4>
<pre class="brush: html"><input type="text" id="myTextField" value="Text field.">
<p></p>
<button type="button" onclick="focusMethod()">点这里将焦点设置到文本框上！</button>
</pre>
<h4 id="结果">结果</h4>
<p>{{ EmbedLiveSample('Focus_on_a_text_field') }}</p>
<h3 id="将焦点设置到按钮上">将焦点设置到按钮上</h3>
<h4 id="JavaScript_2">JavaScript</h4>
<pre>focusMethod = function getFocus() {
document.getElementById("myButton").focus();
}</pre>
<h4 id="HTML_2">HTML</h4>
<pre><button type="button" id="myButton">Click Me!</button>
<p></p>
<button type="button" onclick="focusMethod()">点这里将焦点设置到按钮上！</button></pre>
<h4 id="结果_2">结果</h4>
<p>{{ EmbedLiveSample('Focus_on_a_button') }}</p>
<h3 id="Focus_with_focusOption">Focus with focusOption</h3>
<h4 id="JavaScript_3">JavaScript</h4>
<pre class="brush: js">focusScrollMethod = function getFocus() {
document.getElementById("myButton").focus({preventScroll:false});
}
focusNoScrollMethod = function getFocusWithoutScrolling() {
document.getElementById("myButton").focus({preventScroll:true});
}
</pre>
<h4 id="HTML_3">HTML</h4>
<pre class="brush: html"><button type="button" onclick="focusScrollMethod()">Click me to focus on the button!</button>
<button type="button" onclick="focusNoScrollMethod()">Click me to focus on the button without scrolling!</button>
<div id="container" style="height: 1000px; width: 1000px;">
<button type="button" id="myButton" style="margin-top: 500px;">Click Me!</button>
</div>
</pre>
<h4 id="结果_3">结果</h4>
<p>{{ EmbedLiveSample('Focus_prevent_scroll') }}</p>
<h2 id="规范">规范</h2>
<table class="standard-table">
<thead>
<tr>
<th scope="col">规范</th>
<th scope="col">状态</th>
<th scope="col">备注</th>
</tr>
</thead>
<tbody>
<tr>
<td>{{SpecName('HTML WHATWG', 'editing.html#dom-focus', 'focus')}}</td>
<td>{{Spec2('HTML WHATWG')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('HTML5.1', 'editing.html#focus()-0', 'focus')}}</td>
<td>{{Spec2('HTML5.1')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('HTML5 W3C', 'editing.html#dom-focus', 'focus')}}</td>
<td>{{Spec2('HTML5 W3C')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('DOM2 HTML', 'html.html#ID-32130014', 'focus')}}</td>
<td>{{Spec2('DOM2 HTML')}}</td>
<td></td>
</tr>
<tr>
<td>{{SpecName('DOM1', 'level-one-html.html#method-focus', 'focus')}}</td>
<td>{{Spec2('DOM1')}}</td>
<td></td>
</tr>
</tbody>
</table>
<h2 id="备注">备注</h2>
<ul>
<li>If you call <code>HTMLElement.focus()</code> from a mousedown event handler, you must call <code>event.preventDefault()</code> to keep the focus from leaving the <code>HTMLElement</code></li>
<li>
<p>Behaviour of the focus in relation to different HTML features like {{HTMLAttrxRef("tabindex")}} or {{Glossary("shadow tree","shadow dom", 1)}}, which previously remained under-specified, were recently updated (as October of 2019). Checkout <a href="https://blog.whatwg.org/focusing-on-focus">WHATWG blog</a> for more info.</p>
</li>
</ul>
<h2 id="浏览器兼容性">浏览器兼容性</h2>
<p>{{Compat("api.HTMLElement.focus")}}</p>
<h2 id="参见">参见</h2>
<ul>
<li>DOM method {{domxref("HTMLElement.blur()")}} to remove the focus from an element.</li>
<li>{{ domxref("document.activeElement") }} to know which is the currently focused element.</li>
</ul>
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