---
title: MouseEvent
slug: Web/API/MouseEvent
translation_of: Web/API/MouseEvent
---
<p id="Summary">{{APIRef("DOM Events")}}</p>

<p><code><strong>MouseEvent</strong></code> 介面表示了由使用者經指標裝置（如滑鼠）進行互動所發生的事件。常見的 <code>MouseEvent</code> 實作事件包括了 {{event("click")}}、{{event("dblclick")}}、{{event("mouseup")}} 與 {{event("mousedown")}}。</p>

<p><code>MouseEvent</code> 繼承自 {{domxref("UIEvent")}}，而 <code>UIEvent</code> 則繼承自 {{domxref("Event")}}。雖然 {{domxref("MouseEvent.initMouseEvent()")}} 方法仍然向下相容新的瀏覽器，但現今應該使用 {{domxref("MouseEvent.MouseEvent", "MouseEvent()")}} 建構式來建立 <code>MouseEvent</code> 物件。</p>

<p>另外還有一些特定的事件繼承自 <code>MouseEvent</code>：{{domxref("WheelEvent")}} 及 {{domxref("DragEvent")}}。</p>

<h2 id="建構式">建構式</h2>

<dl>
 <dt>{{domxref("MouseEvent.MouseEvent", "MouseEvent()")}}</dt>
 <dd>建立一個 <code>MouseEvent</code> 物件。</dd>
</dl>

<h2 id="屬性">屬性</h2>

<p><em>此介面也繼承了其父介面 {{domxref("UIEvent")}} 與 {{domxref("Event")}} 的屬性</em></p>

<dl>
 <dt>{{domxref("MouseEvent.altKey")}} {{readonlyinline}}</dt>
 <dd>Returns <code>true</code> if the <kbd>alt</kbd> key was down when the mouse event was fired.</dd>
 <dt>{{domxref("MouseEvent.button")}} {{readonlyinline}}</dt>
 <dd>The button number that was pressed when the mouse event was fired. </dd>
 <dt>{{domxref("MouseEvent.buttons")}} {{readonlyinline}} {{gecko_minversion_inline("15.0")}}</dt>
 <dd>
 <p>The buttons being pressed when the mouse event was fired</p>
 </dd>
 <dt>{{domxref("MouseEvent.clientX")}} {{readonlyinline}}</dt>
 <dd>The X coordinate of the mouse pointer in local (DOM content) coordinates.</dd>
 <dt>{{domxref("MouseEvent.clientY")}} {{readonlyinline}}</dt>
 <dd>The Y coordinate of the mouse pointer in local (DOM content) coordinates.</dd>
 <dt>{{domxref("MouseEvent.ctrlKey")}} {{readonlyinline}}</dt>
 <dd>Returns <code>true</code> if the <kbd>control</kbd> key was down when the mouse event was fired.</dd>
 <dt>{{domxref("MouseEvent.metaKey")}} {{readonlyinline}}</dt>
 <dd>Returns <code>true</code> if the <kbd>meta</kbd> key was down when the mouse event was fired.</dd>
 <dt>{{domxref("MouseEvent.movementX")}} {{readonlyinline}}</dt>
 <dd>The X coordinate of the mouse pointer relative to the position of the last {{event("mousemove")}} event.</dd>
 <dt>{{domxref("MouseEvent.movementY")}} {{readonlyinline}}</dt>
 <dd>The Y coordinate of the mouse pointer relative to the position of the last {{event("mousemove")}} event.</dd>
 <dt>{{domxref("MouseEvent.offsetX")}} {{readonlyinline}}{{experimental_inline}}</dt>
 <dd>The X coordinate of the mouse pointer relative to the position of the padding edge of the target node.</dd>
 <dt>{{domxref("MouseEvent.offsetY")}} {{readonlyinline}}{{experimental_inline}}</dt>
 <dd>The Y coordinate of the mouse pointer relative to the position of the padding edge of the target node.</dd>
 <dt>{{domxref("MouseEvent.pageX")}} {{readonlyinline}}{{experimental_inline}}</dt>
 <dd>The X coordinate of the mouse pointer relative to the whole document.</dd>
 <dt>{{domxref("MouseEvent.pageY")}} {{readonlyinline}}{{experimental_inline}}</dt>
 <dd>The Y coordinate of the mouse pointer relative to the whole document.</dd>
 <dt>{{domxref("MouseEvent.region")}} {{readonlyinline}}</dt>
 <dd>Returns the id of the hit region affected by the event. If no hit region is affected, <code>null</code> is returned.</dd>
 <dt>{{domxref("MouseEvent.relatedTarget")}} {{readonlyinline}}</dt>
 <dd>
 <p>The secondary target for the event, if there is one.</p>
 </dd>
 <dt>{{domxref("MouseEvent.screenX")}} {{readonlyinline}}</dt>
 <dd>The X coordinate of the mouse pointer in global (screen) coordinates.</dd>
 <dt>{{domxref("MouseEvent.screenY")}} {{readonlyinline}}</dt>
 <dd>The Y coordinate of the mouse pointer in global (screen) coordinates.</dd>
 <dt>{{domxref("MouseEvent.shiftKey")}} {{readonlyinline}}</dt>
 <dd>Returns <code>true</code> if the <kbd>shift</kbd> key was down when the mouse event was fired.</dd>
 <dt>{{domxref("MouseEvent.which")}} {{non-standard_inline}} {{readonlyinline}}</dt>
 <dd>The button being pressed when the mouse event was fired.</dd>
 <dt>{{domxref("MouseEvent.mozPressure")}} {{non-standard_inline()}} {{readonlyinline}}</dt>
 <dd>The amount of pressure applied to a touch or tablet device when generating the event; this value ranges between <code>0.0</code> (minimum pressure) and <code>1.0</code> (maximum pressure).</dd>
 <dt>{{domxref("MouseEvent.mozInputSource")}} {{non-standard_inline()}} {{readonlyinline}}</dt>
 <dd>
 <p>The type of device that generated the event (one of the <code>MOZ_SOURCE_*</code> constants listed below). This lets you, for example, determine whether a mouse event was generated by an actual mouse or by a touch event (which might affect the degree of accuracy with which you interpret the coordinates associated with the event).</p>
 </dd>
 <dt>{{domxref("MouseEvent.webkitForce")}} {{non-standard_inline()}} {{readonlyinline}}</dt>
 <dd>The amount of pressure applied when clicking</dd>
 <dt>{{domxref("MouseEvent.x")}} {{experimental_inline}}{{readonlyinline}}</dt>
 <dd>Alias for {{domxref("MouseEvent.clientX")}}.</dd>
 <dt>{{domxref("MouseEvent.y")}} {{experimental_inline}}{{readonlyinline}}</dt>
 <dd>Alias for {{domxref("MouseEvent.clientY")}}</dd>
</dl>

<h2 id="Constants">Constants</h2>

<dl>
 <dt>{{domxref("MouseEvent.WEBKIT_FORCE_AT_MOUSE_DOWN")}} {{non-standard_inline}}{{readonlyinline}}</dt>
 <dd>Minimum force necessary for a normal click</dd>
 <dt>{{domxref("MouseEvent.WEBKIT_FORCE_AT_FORCE_MOUSE_DOWN")}} {{non-standard_inline}}{{readonlyinline}}</dt>
 <dd>Minimum force necessary for a force click</dd>
</dl>

<h2 id="方法">方法</h2>

<p><em>此介面也繼承了其父介面 {{domxref("UIEvent")}} 與 {{domxref("Event")}} 的方法</em></p>

<dl>
 <dt>{{domxref("MouseEvent.getModifierState()")}}</dt>
 <dd>Returns the current state of the specified modifier key. See the {{domxref("KeyboardEvent.getModifierState")}}() for details.</dd>
 <dt>{{domxref("MouseEvent.initMouseEvent()")}} {{deprecated_inline}}</dt>
 <dd>Initializes the value of a <code>MouseEvent</code> created. If the event has already being dispatched, this method does nothing.</dd>
</dl>

<h2 id="範例">範例</h2>

<p>This example demonstrates simulating a click (that is programmatically generating a click event) on a checkbox using DOM methods. </p>

<pre class="brush: js">function simulateClick() {
  var evt = new <a href="/en-US/docs/Web/API/MouseEvent">MouseEvent</a>("click", {
    bubbles: true,
    cancelable: true,
    view: window
  });
  var cb = document.getElementById("checkbox"); //element to click on
  var canceled = !cb.<a href="/en-US/docs/Web/API/EventTarget.dispatchEvent" rel="internal" title="en/DOM/element.dispatchEvent">dispatchEvent</a>(evt);
  if(canceled) {
    // A handler called preventDefault
    alert("canceled");
  } else {
    // None of the handlers called preventDefault
    alert("not canceled");
  }
}
document.getElementById("button").addEventListener('click', simulateClick);</pre>

<pre class="brush: html">&lt;p&gt;&lt;label&gt;&lt;input type="checkbox" id="checkbox"&gt; Checked&lt;/label&gt;
&lt;p&gt;&lt;button id="button"&gt;Click me&lt;/button&gt;</pre>

<p>Click on the button to see how the sample works:</p>

<p>{{ EmbedLiveSample('Example', '', '', '') }}</p>

<h2 id="規範">規範</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('CSSOM View','#extensions-to-the-mouseevent-interface', 'MouseEvent')}}</td>
   <td>{{Spec2('CSSOM View')}}</td>
   <td>Redefines <code>MouseEvent</code> from long to double. This means that a <code>PointerEvent</code> whose <code>pointerType</code> is mouse will be a double.</td>
  </tr>
  <tr>
   <td>{{SpecName("HTML WHATWG", "#dom-mouseevent-region", "MouseEvent.region")}}</td>
   <td>{{Spec2('HTML WHATWG')}}</td>
   <td>From {{SpecName('DOM3 Events')}}, added the <code>region</code> property.</td>
  </tr>
  <tr>
   <td>{{SpecName('Pointer Lock','#extensions-to-the-mouseevent-interface','MouseEvent')}}</td>
   <td>{{Spec2('Pointer Lock')}}</td>
   <td>From {{SpecName('DOM3 Events')}}, added <code>movementX</code> and <code>movementY</code> properties.</td>
  </tr>
  <tr>
   <td>{{SpecName('CSSOM View', '#extensions-to-the-mouseevent-interface', 'MouseEvent')}}</td>
   <td>{{Spec2('CSSOM View')}}</td>
   <td>From {{SpecName('DOM3 Events')}}, added <code>offsetX</code> and <code>offsetY</code>, <code>pageX</code> and <code>pageY</code>, <code>x,</code> and <code>y</code> properties. Redefined screen, page, client and coordinate (x and y) properties as <code>double</code> from <code>long</code>.</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM3 Events','#events-mouseevents','MouseEvent')}}</td>
   <td>{{Spec2('DOM3 Events')}}</td>
   <td>From {{SpecName('DOM2 Events')}}, added the <code>MouseEvent()</code> constructor, the <code>getModifierState()</code> method and the <code>buttons</code> property.</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM2 Events','#Events-MouseEvent','MouseEvent')}}</td>
   <td>{{Spec2('DOM2 Events')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility" name="Browser_compatibility">瀏覽器相容性</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>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.movementX","movementX")}}<br>
    {{domxref("MouseEvent.movementY","movementY")}}</td>
   <td>{{CompatChrome(37)}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}} {{property_prefix("moz")}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
  <tr>
   <td>{{ domxref("MouseEvent.buttons", "buttons") }}</td>
   <td>{{CompatChrome(43)}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{CompatNo}}</td>
  </tr>
  <tr>
   <td>{{ domxref("MouseEvent.which", "which") }}</td>
   <td>{{CompatChrome(1)}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>1.0</td>
   <td>9.0</td>
   <td>5.0</td>
   <td>1.0</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.getModifierState()", "getModifierState()")}}</td>
   <td>{{CompatChrome(47)}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatGeckoDesktop(15)}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.mozPressure", "mozPressure")}} and {{domxref("MouseEvent.mozInputSource", "mozInputSource")}} {{non-standard_inline}}</td>
   <td>{{CompatNo}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{CompatGeckoDesktop(2)}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.MouseEvent", "MouseEvent()")}}</td>
   <td>{{CompatChrome(45)}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{CompatGeckoDesktop(11)}}</td>
   <td>9.0</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.region")}}</td>
   <td>{{CompatChrome(51)}}<sup>[1]</sup></td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{CompatGeckoDesktop(32)}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.offsetX")}}, and {{domxref("MouseEvent.offsetY")}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>9</td>
   <td>{{CompatGeckoDesktop(40)}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
  <tr>
   <td>{{domxref("MouseEvent.screenX")}}, {{domxref("MouseEvent.screenY")}}, {{domxref("MouseEvent.clientX")}}, and {{domxref("MouseEvent.Y")}} are double instead of long.</td>
   <td>{{CompatChrome(56)}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</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>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
 </tbody>
</table>
</div>

<p>[1] Requires enabling the <code>ExperimentalCanvasFeatures</code> flag.</p>

<h2 id="參見">參見</h2>

<ul>
 <li>Its direct parent, {{domxref("UIEvent")}}.</li>
</ul>