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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">:first Selector</h1>
<div class="entry-meta jq-clearfix">
Categories:
<span class="category"><a href="http://api.jquery.com/category/selectors/" title="View all posts in Selectors">Selectors</a> > <a href="http://api.jquery.com/category/selectors/basic-filter-selectors/" title="View all posts in Basic Filter">Basic Filter</a></span> | <span class="category"><a href="http://api.jquery.com/category/selectors/" title="View all posts in Selectors">Selectors</a> > <a href="http://api.jquery.com/category/selectors/jquery-selector-extensions/" title="View all posts in jQuery Extensions">jQuery Extensions</a></span>
</div>
</div>
<div id="first1" class="entry selector">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">first</span> selector</h2>
<div class="jq-box roundBottom entry-details">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.0/">1.0</a></span>jQuery(':first')</h4>
<p class="desc"><strong>Description: </strong>Selects the first matched element.</p>
<div class="longdesc"><p>The <code>:first</code> pseudo-class is equivalent to <code>:eq(0)</code>. It could also be written as <code>:lt(1)</code>. While this matches only a single element, <a href="first-child-selector">:first-child</a> can match more than one: One for each parent.</p></div>
<h3 id="notes-0">Additional Notes:</h3>
<div class="longdesc"><ul><li>Because <code>:first</code> is a jQuery extension and not part of the CSS specification, queries using <code>:first</code> cannot take advantage of the performance boost provided by the native DOM <code>querySelectorAll()</code> method. To achieve the best performance when using <code>:first</code> to select elements, first select the elements using a pure CSS selector, then use <a href="http://api.jquery.com/filter/"><code>.filter(":first")</code></a>.</li></ul></div>
<h3>Example:</h3>
<div class="entry-examples" id="entry-examples"><div id="example-0">
<h4><span class="desc">Finds the first table row.</span></h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<style>
td { color:blue; font-weight:bold; }
</style>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<table>
<tr><td>Row 1</td></tr>
<tr><td>Row 2</td></tr>
<tr><td>Row 3</td></tr>
</table>
<script>$("tr:first").css("font-style", "italic");</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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