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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">.has()</h1>
<div class="entry-meta jq-clearfix">
Categories:
<span class="category"><a href="http://api.jquery.com/category/traversing/" title="View all posts in Traversing">Traversing</a> > <a href="http://api.jquery.com/category/traversing/filtering/" title="View all posts in Filtering">Filtering</a></span>
</div>
</div>
<div id="has1" class="entry method">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">.has( selector )</span> <span class="returns">Returns: <a class="return" href="http://api.jquery.com/Types/#jQuery">jQuery</a></span>
</h2>
<div class="jq-box roundBottom entry-details">
<p class="desc"><strong>Description: </strong>Reduce the set of matched elements to those that have a descendant that matches the selector or DOM element.</p>
<ul class="signatures">
<li class="signature" id="has-selector">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.4/">1.4</a></span>.has( selector )</h4>
<p class="arguement"><strong>selector</strong>A string containing a selector expression to match elements against.</p>
</li>
<li class="signature" id="has-contained">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.4/">1.4</a></span>.has( contained )</h4>
<p class="arguement"><strong>contained</strong>A DOM element to match elements against.</p>
</li>
</ul>
<div class="longdesc">
<p>Given a jQuery object that represents a set of DOM elements, the <code>.has()</code> method constructs a new jQuery object from a subset of the matching elements. The supplied selector is tested against the descendants of the matching elements; the element will be included in the result if any of its descendant elements matches the selector.</p>
<p>Consider a page with a nested list as follows:</p>
<pre>
<ul>
<li>list item 1</li>
<li>list item 2
<ul>
<li>list item 2-a</li>
<li>list item 2-b</li>
</ul>
</li>
<li>list item 3</li>
<li>list item 4</li>
</ul>
</pre>
<p>We can apply this method to the set of list items as follows:</p>
<pre>$('li').has('ul').css('background-color', 'red');</pre>
<p>The result of this call is a red background for item 2, as it is the only <code><li></code> that has a <code><ul></code> among its descendants.</p>
</div>
<h3>Example:</h3>
<div class="entry-examples" id="entry-examples"><div id="example-0">
<h4><span class="desc">Check if an element is inside another.</span></h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<style>
.full { border: 1px solid red; }
</style>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<ul><li>Does the UL contain an LI?</li></ul>
<script>
$("ul").append("<li>" + ($("ul").has("li").length ? "Yes" : "No") + "</li>");
$("ul").has("li").addClass("full");
</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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