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---
title: EventTarget
slug: Web/API/EventTarget
tags:
- API
- DOM
- DOM Events
- Interface
- NeedsTranslation
- TopicStub
translation_of: Web/API/EventTarget
---
<p>{{ApiRef("DOM Events")}}</p>
<p><code>EventTarget</code> is an interface implemented by objects that can receive events and may have listeners for them.</p>
<p>{{domxref("Element")}}, {{domxref("document")}}, and {{domxref("window")}} are the most common event targets, but other objects can be event targets too, for example {{domxref("XMLHttpRequest")}}, {{domxref("AudioNode")}}, {{domxref("AudioContext")}}, and others.</p>
<p>Many event targets (including elements, documents, and windows) also support setting <a href="/en-US/docs/Web/Guide/DOM/Events/Event_handlers">event handlers</a> via <code>on...</code> properties and attributes.</p>
<h2 id="Methods">Methods</h2>
<dl>
<dt>{{domxref("EventTarget.addEventListener()")}}</dt>
<dd>Register an event handler of a specific event type on the <code>EventTarget</code>.</dd>
<dt>{{domxref("EventTarget.removeEventListener()")}}</dt>
<dd>Removes an event listener from the <code>EventTarget</code>.</dd>
<dt>{{domxref("EventTarget.dispatchEvent()")}}</dt>
<dd>Dispatch an event to this <code>EventTarget</code>.</dd>
</dl>
<h3 id="Additional_methods_for_Mozilla_chrome_code">Additional methods for Mozilla chrome code</h3>
<p>Mozilla extensions for use by JS-implemented event targets to implement on* properties. See also <a href="/en-US/docs/Mozilla/WebIDL_bindings">WebIDL bindings</a>.</p>
<ul>
<li>void <strong>setEventHandler</strong>(DOMString type, EventHandler handler) {{non-standard_inline}}</li>
<li>EventHandler <strong>getEventHandler</strong>(DOMString type) {{non-standard_inline}}</li>
</ul>
<h2 id="Example">Example:</h2>
<h3 id="_Simple_implementation_of_EventTarget" name="_Simple_implementation_of_EventTarget">Simple implementation of EventTarget</h3>
<pre class="brush: js">var EventTarget = function() {
this.listeners = {};
};
EventTarget.prototype.listeners = null;
EventTarget.prototype.addEventListener = function(type, callback) {
if (!(type in this.listeners)) {
this.listeners[type] = [];
}
this.listeners[type].push(callback);
};
EventTarget.prototype.removeEventListener = function(type, callback) {
if (!(type in this.listeners)) {
return;
}
var stack = this.listeners[type];
for (var i = 0, l = stack.length; i < l; i++) {
if (stack[i] === callback){
stack.splice(i, 1);
return;
}
}
};
EventTarget.prototype.dispatchEvent = function(event) {
if (!(event.type in this.listeners)) {
return true;
}
var stack = this.listeners[event.type];
event.target = this;
for (var i = 0, l = stack.length; i < l; i++) {
stack[i].call(this, event);
}
return !event.defaultPrevented;
};
</pre>
<p>{{ EmbedLiveSample('_Simple_implementation_of_EventTarget') }}</p>
<h2 id="Specifications">Specifications</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('DOM WHATWG', '#interface-eventtarget', 'EventTarget')}}</td>
<td>{{Spec2('DOM WHATWG')}}</td>
<td>No change.</td>
</tr>
<tr>
<td>{{SpecName('DOM3 Events', 'DOM3-Events.html#interface-EventTarget', 'EventTarget')}}</td>
<td>{{Spec2('DOM3 Events')}}</td>
<td>A few parameters are now optional (<code>listener</code>), or accepts the <code>null</code> value (<code>useCapture</code>).</td>
</tr>
<tr>
<td>{{SpecName('DOM2 Events', 'events.html#Events-EventTarget', 'EventTarget')}}</td>
<td>{{Spec2('DOM2 Events')}}</td>
<td>Initial definition.</td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</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 (WebKit)</th>
</tr>
<tr>
<td>Basic support</td>
<td>1.0</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatGeckoDesktop("1")}}</td>
<td>9.0</td>
<td>7</td>
<td>1.0<sup>[1]</sup></td>
</tr>
</tbody>
</table>
</div>
<div id="compat-mobile">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>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>1.0</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatGeckoMobile("1")}}</td>
<td>9.0</td>
<td>6.0</td>
<td>1.0</td>
</tr>
</tbody>
</table>
</div>
<p>[1] <code>window.EventTarget</code> does not exist.</p>
<h2 id="See_Also">See Also</h2>
<ul>
<li><a href="/en-US/docs/Web/Reference/Events">Event reference</a> - the events available in the platform.</li>
<li><a href="/en-US/docs/Web/Guide/DOM/Events">Event developer guide</a></li>
<li>{{domxref("Event")}} interface</li>
</ul>
|
