files/zh-cn/web/api/element/setpointercapture/index.html


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---
title: Element.setPointerCapture()
slug: Web/API/Element/setPointerCapture
tags:
  - API
  - DOM
  - Element
translation_of: Web/API/Element/setPointerCapture
---
<p>{{APIRef("DOM")}}</p>

<p>{{domxref("Element")}}接口的<strong><code>setPointerCapture()</code></strong> 方法用于将特定元素指定为未来指针事件的捕获目标。指针的后续事件将以捕获元素为目标，直到捕获被释放（通过{{domxref("Element.releasePointerCapture()")}}）。</p>

<div class="note">一旦设置了pointer capture,  {{event("pointerover")}}, {{event("pointerout")}} {{event("pointerenter")}}, 和{{event("pointerleave")}}  事件将不会被触发，直到越过设置了capture的元素的边界。这是因为其他元素将不能再作为pointer事件的目标了。这会影响到这些事件在其他元素上的触发。</div>

<div>
<h3 id="指针捕获概述">指针捕获概述</h3>
</div>

<div>指针捕获允许一个特定的指针事件({{domxref("PointerEvent")}}) 事件从一个事件触发时候的目标重定位到另一个目标上。这个功能可以确保一个元素可以持续的接收到一个pointer事件，即使这个事件的触发点已经移出了这个元素（比如，在滚动的时候）。</div>

<h2 id="语法">语法</h2>

<pre class="syntaxbox">targetElement.<em>setPointerCapture</em>(pointerId);
</pre>

<h3 id="参数">参数</h3>

<dl>
 <dt><code>pointerId</code></dt>
 <dd>{{domxref("PointerEvent")}} 对象的{{domxref("PointerEvent.pointerId", "pointerId")}} 。</dd>
</dl>

<h3 id="返回值">返回值</h3>

<p>返回void。如果<code>pointerId</code>不匹配任何当前活动的指针事件，将抛出{{domxref("DOMException")}}。</p>

<h2 id="示例">示例</h2>

<p>当您按下它时，此示例在 {{HtmlElement("div")}} 上设置指针捕获。这使您可以滑动元素，即使指针移动到其边界之外也是如此。</p>

<h3 id="HTML">HTML</h3>

<pre class="brush: html">&lt;div id="slider"&gt;SLIDE ME&lt;/div&gt;</pre>

<h3 id="CSS">CSS</h3>

<pre class="brush: css">div {
  width: 140px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fbe;
}</pre>

<h3 id="JavaScript">JavaScript</h3>

<pre class="brush: js">function beginSliding(e) {
  slider.onpointermove = slide;
  slider.setPointerCapture(e.pointerId);
}

function stopSliding(e) {
  slider.onpointermove = null;
  slider.releasePointerCapture(e.pointerId);
}

function slide(e) {
  slider.style.transform = `translate(${e.clientX - 70}px)`;
}

const slider = document.getElementById('slider');

slider.onpointerdown = beginSliding;
slider.onpointerup = stopSliding;</pre>

<h3 id="结果">结果</h3>

<p>{{EmbedLiveSample("示例")}}</p>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">标准</th>
   <th scope="col">状态</th>
   <th scope="col">备注</th>
  </tr>
  <tr>
   <td>{{SpecName('Pointer Events 2','#widl-Element-setPointerCapture-void-long-pointerId', 'setPointerCapture')}}</td>
   <td>{{Spec2('Pointer Events 2')}}</td>
   <td>不稳定版本</td>
  </tr>
  <tr>
   <td>{{SpecName('Pointer Events', '#widl-Element-setPointerCapture-void-long-pointerId', 'setPointerCapture')}}</td>
   <td>{{Spec2('Pointer Events')}}</td>
   <td>初版</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

<p>{{Compat("api.Element.setPointerCapture")}}</p>

<h2 id="参见">参见</h2>

<ul>
 <li>{{ domxref("Element.releasePointerCapture")}}</li>
 <li>{{ domxref("Pointer_events","Pointer Events") }}</li>
</ul>