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<h1 class="jq-clearfix">.unload()</h1>
<div class="entry-meta jq-clearfix">
Categories:
<span class="category"><a href="http://api.jquery.com/category/events/" title="View all posts in Events">Events</a> > <a href="http://api.jquery.com/category/events/document-loading/" title="View all posts in Document Loading">Document Loading</a></span>
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<div id="unload1" class="entry method">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">.unload( handler(eventObject) )</span> <span class="returns">Returns: <a class="return" href="http://api.jquery.com/Types/#jQuery">jQuery</a></span>
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<div class="jq-box roundBottom entry-details">
<p class="desc"><strong>Description: </strong>Bind an event handler to the "unload" JavaScript event.</p>
<ul class="signatures">
<li class="signature" id="unload-handlereventObject">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.0/">1.0</a></span>.unload( handler(eventObject) )</h4>
<p class="arguement"><strong>handler(eventObject)</strong>A function to execute when the event is triggered.</p>
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<li class="signature" id="unload-eventData-handlereventObject">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.4.3/">1.4.3</a></span>.unload( [eventData], handler(eventObject) )</h4>
<p class="arguement"><strong>eventData</strong>A map of data that will be passed to the event handler.</p>
<p class="arguement"><strong>handler(eventObject)</strong>A function to execute each time the event is triggered.</p>
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<div class="longdesc">
<p>This method is a shortcut for <code>.bind('unload', handler)</code>.</p>
<p>The <code>unload</code> event is sent to the <code>window</code> element when the user navigates away from the page. This could mean one of many things. The user could have clicked on a link to leave the page, or typed in a new URL in the address bar. The forward and back buttons will trigger the event. Closing the browser window will cause the event to be triggered. Even a page reload will first create an <code>unload</code> event.</p>
<blockquote><p>The exact handling of the <code>unload</code> event has varied from version to version of browsers. For example, some versions of Firefox trigger the event when a link is followed, but not when the window is closed. In practical usage, behavior should be tested on all supported browsers, and contrasted with the proprietary <code>beforeunload</code> event.</p></blockquote>
<p>Any <code>unload</code> event handler should be bound to the <code>window</code> object:</p>
<pre>$(window).unload(function() {
alert('Handler for .unload() called.');
});
</pre>
<p>After this code executes, the alert will be displayed whenever the browser leaves the current page.
It is not possible to cancel the <code>unload</code> event with <code>.preventDefault()</code>. This event is available so that scripts can perform cleanup when the user leaves the page.
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<h3>Example:</h3>
<div class="entry-examples" id="entry-examples"><div id="example-0">
<h4><span class="desc">To display an alert when a page is unloaded:</span></h4>
<pre class="prettyprint"><code class="example">$(window).unload( function () { alert("Bye now!"); } );</code></pre>
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