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<!DOCTYPE html>
<html lang='en'><head><meta http-equiv='content-type' content='text/html; charset=UTF-8' /></head><body>
<div class="entry-content">
<div class="entry-title roundTop">
<h1 class="jq-clearfix">jQuery.hasData()</h1>
<div class="entry-meta jq-clearfix">
Categories:
<span class="category"><a href="http://api.jquery.com/category/data/" title="View all posts in Data">Data</a></span>
</div>
</div>
<div id="jQuery-hasData1" class="entry method">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">jQuery.hasData( element )</span> <span class="returns">Returns: <a class="return" href="http://api.jquery.com/Types/#Boolean">Boolean</a></span>
</h2>
<div class="jq-box roundBottom entry-details">
<p class="desc"><strong>Description: </strong>Determine whether an element has any jQuery data associated with it.</p>
<ul class="signatures"><li class="signature" id="jQuery-hasData-element">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.5/">1.5</a></span>jQuery.hasData( element )</h4>
<p class="arguement"><strong>element</strong>A DOM element to be checked for data.</p>
</li></ul>
<div class="longdesc">
<p>The <code>jQuery.hasData()</code> method provides a way to determine if an element currently has any values that were set using <code><a href="/jQuery.data">jQuery.data()</a></code>. If no data is associated with an element (there is no data object at all or the data object is empty), the method returns <code>false</code>; otherwise it returns <code>true</code>.</p>
<p>The primary advantage of <code>jQuery.hasData(element)</code> is that it does not create and associate a data object with the element if none currently exists. In contrast, <code>jQuery.data(element)</code> always returns a data object to the caller, creating one if no data object previously existed.
</p>
</div>
<h3>Example:</h3>
<div class="entry-examples" id="entry-examples"><div id="example-0">
<h4><span class="desc">Set data on an element and see the results of hasData.</span></h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<p>Results: </p>
<script>
$(function(){
var $p = jQuery("p"), p = $p[0];
$p.append(jQuery.hasData(p)+" "); /* false */
jQuery.data(p, "testing", 123);
$p.append(jQuery.hasData(p)+" "); /* true*/
jQuery.removeData(p, "testing");
$p.append(jQuery.hasData(p)+" "); /* false */
});
</script>
</body>
</html></code></pre>
<h4>Demo:</h4>
<div class="demo code-demo"></div>
</div></div>
</div>
</div>
</div>
</body></html>
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