Revision 923667 of CloseEvent

<p>{{APIRef("Websockets API")}}</p>

<p>A <code>CloseEvent</code> is sent to clients using {{Glossary("WebSockets")}} when the connection is closed. This is delivered to the listener indicated by the <code>WebSocket</code> object's <code>onclose</code> attribute.</p>

<h2 id="Constructor">Constructor</h2>

<dl>
 <dt>{{domxref("CloseEvent.CloseEvent", "CloseEvent()")}}</dt>
 <dd>Creates a new <code>CloseEvent</code>.</dd>
</dl>

<h2 id="Properties">Properties</h2>

<p><em>This interface also inherits properties from its parent, {{domxref("Event")}}.</em></p>

<dl>
 <dt>{{domxref("CloseEvent.code")}} {{readOnlyInline}}</dt>
 <dd>Returns an <code>unsigned short</code> containing the close code send by the server. The following values are permitted status codes.
 <table class="standard-table" id="Status_codes">
  <tbody>
   <tr>
    <td class="header">Status code</td>
    <td class="header">Name</td>
    <td class="header">Description</td>
   </tr>
   <tr>
    <td><code>0</code>–<code>999</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved and not used.</strong></td>
   </tr>
   <tr>
    <td><code>1000</code></td>
    <td><code>CLOSE_NORMAL</code></td>
    <td>Normal closure; the connection successfully completed whatever purpose for which it was created.</td>
   </tr>
   <tr>
    <td><code>1001</code></td>
    <td><code>CLOSE_GOING_AWAY</code></td>
    <td>The endpoint is going away, either because of a server failure or because the browser is navigating away from the page that opened the connection.</td>
   </tr>
   <tr>
    <td><code>1002</code></td>
    <td><code>CLOSE_PROTOCOL_ERROR</code></td>
    <td>The endpoint is terminating the connection due to a protocol error.</td>
   </tr>
   <tr>
    <td><code>1003</code></td>
    <td><code>CLOSE_UNSUPPORTED</code></td>
    <td>The connection is being terminated because the endpoint received data of a type it cannot accept (for example, a text-only endpoint received binary data).</td>
   </tr>
   <tr>
    <td><code>1004</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved.</strong> A meaning might be defined in the future.</td>
   </tr>
   <tr>
    <td><code>1005</code></td>
    <td><code>CLOSE_NO_STATUS</code></td>
    <td><strong>Reserved.</strong>&nbsp; Indicates that no status code was provided even though one was expected.</td>
   </tr>
   <tr>
    <td><code>1006</code></td>
    <td><code>CLOSE_ABNORMAL</code></td>
    <td><strong>Reserved.</strong> Used to indicate that a connection was closed abnormally (that is, with no close frame being sent) when a status code is expected.</td>
   </tr>
   <tr>
    <td><code>1007</code></td>
    <td>&nbsp;</td>
    <td>The endpoint is terminating the connection because a message was received that contained inconsistent data (e.g., non-UTF-8 data within a text message).</td>
   </tr>
   <tr>
    <td><code>1008</code></td>
    <td>&nbsp;</td>
    <td>The endpoint is terminating the connection because it received a message that violates its policy. This is a generic status code, used when codes 1003 and 1009 are not suitable.</td>
   </tr>
   <tr>
    <td><code>1009</code></td>
    <td><code>CLOSE_TOO_LARGE</code></td>
    <td>The endpoint is terminating the connection because a data frame was received that is too large.</td>
   </tr>
   <tr>
    <td><code>1010</code></td>
    <td>&nbsp;</td>
    <td>The client is terminating the connection because it expected the server to negotiate one or more extension, but the server didn't.</td>
   </tr>
   <tr>
    <td><code>1011</code></td>
    <td>&nbsp;</td>
    <td>The server is terminating the connection because it encountered an unexpected condition that prevented it from fulfilling the request.</td>
   </tr>
   <tr>
    <td><code>1012</code>–<code>1014</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved for future use by the WebSocket standard.</strong></td>
   </tr>
   <tr>
    <td><code>1015</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved.</strong> Indicates that the connection was closed due to a failure to perform a TLS handshake (e.g., the server certificate can't be verified).</td>
   </tr>
   <tr>
    <td><code>1016</code>–<code>1999</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved for future use by the WebSocket standard.</strong></td>
   </tr>
   <tr>
    <td><code>2000</code>–<code>2999</code></td>
    <td>&nbsp;</td>
    <td><strong>Reserved for use by WebSocket extensions.</strong></td>
   </tr>
   <tr>
    <td><code>3000</code>–<code>3999</code></td>
    <td>&nbsp;</td>
    <td>Available for use by libraries and frameworks. <strong>May not</strong> be used by applications.</td>
   </tr>
   <tr>
    <td><code>4000</code>–<code>4999</code></td>
    <td>&nbsp;</td>
    <td>Available for use by applications.</td>
   </tr>
  </tbody>
 </table>
 </dd>
 <dt>{{domxref("CloseEvent.reason")}} {{readOnlyInline}}</dt>
 <dd>Returns a {{domxref("DOMString")}} indicating the reason the server closed the connection. This is specific to the particular server and sub-protocol.</dd>
 <dt>{{domxref("CloseEvent.wasClean")}} {{readOnlyInline}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} that Indicates whether or not the connection was cleanly closed.</dd>
</dl>

<h2 id="Methods">Methods</h2>

<p><em>This interface also inherits methods from its parent, {{domxref("Event")}}.</em></p>

<dl>
 <dt>{{domxref("CloseEvent.initCloseEvent()")}} {{Non-standard_inline}} {{Obsolete_inline}}</dt>
 <dd>Initializes the value of a <code>CloseEvent</code> created. If the event has already being dispatched, this method does nothing. Do not use this method anymore, use the {{domxref("CloseEvent.CloseEvent", "CloseEvent()")}} constructor instead.</dd>
</dl>

<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>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatGeckoDesktop("8.0")}}<sup>[1]</sup><br />
    {{CompatGeckoDesktop("12.0")}}<sup>[2]</sup></td>
   <td>10</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
  <tr>
   <td><code>initCloseEvent</code><code>()</code> {{Non-standard_inline}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatGeckoDesktop("8.0")}}<br />
    {{CompatNo}} 41.0</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Android</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>{{CompatUnknown}}</td>
   <td>{{CompatGeckoMobile("8.0")}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
  <tr>
   <td><code>initCloseEvent</code><code>()</code> {{Non-standard_inline}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatGeckoMobile("8.0")}}<br />
    {{CompatNo}} 41.0</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
   <td>{{CompatNo}}</td>
  </tr>
 </tbody>
</table>
</div>

<p>[1] Prior to Gecko 8.0 {{geckoRelease("8.0")}},&nbsp;Gecko sent the WebSocket {{event("close")}} event to the listener as a simple event. Support for <code>CloseEvent</code> was implemented in Gecko 8.0.</p>

<p>[2] Prior to Gecko 12.0 {{geckoRelease("12.0")}}, Gecko reported the close code <code>CLOSE_NORMAL</code> when the channel was closed due to an unexpected error, or if it was closed due to an error condition that the specification doesn't cover. Now <code>CLOSE_GOING_AWAY</code> is reported instead.</p>

<h2 id="See_also">See also</h2>

<ul>
 <li><a href="/en-US/docs/Web/API/WebSocket"><code>WebSocket</code></a></li>
</ul>