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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">.prev()</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/tree-traversal/" title="View all posts in Tree Traversal">Tree Traversal</a></span>
</div>
</div>
<div id="prev1" class="entry method">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">.prev( [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>Get the immediately preceding sibling of each element in the set of matched elements, optionally filtered by a selector.</p>
<ul class="signatures"><li class="signature" id="prev-selector">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.0/">1.0</a></span>.prev( [selector] )</h4>
<p class="arguement"><strong>selector</strong>A string containing a selector expression to match elements against.</p>
</li></ul>
<div class="longdesc">
<p>Given a jQuery object that represents a set of DOM elements, the <code>.prev()</code> method searches for the predecessor of each of these elements in the DOM tree and constructs a new jQuery object from the matching elements.</p>
<p>The method optionally accepts a selector expression of the same type that can be passed to the <code>$()</code> function. If the selector is supplied, the preceding element will be filtered by testing whether it match the selector.</p>
<p>Consider a page with a simple list on it:</p>
<pre>
<ul>
<li>list item 1</li>
<li>list item 2</li>
<li class="third-item">list item 3</li>
<li>list item 4</li>
<li>list item 5</li>
</ul>
</pre>
<p>To select the element that comes immediately before item three:</p>
<pre>$('li.third-item').prev().css('background-color', 'red');</pre>
<p>The result of this call is a red background behind item 2. Since no selector expression is supplied, this preceding element is unequivocally included as part of the object. If one had been supplied, the element would be tested for a match before it was included.</p>
<p>If no previous sibling exists, or if the previous sibling element does not match a supplied selector, an empty jQuery object is returned.</p>
<p>To select <em>all</em> preceding sibling elements, rather than just the preceding <em>adjacent</em> sibling, use the <a href="http://api.jquery.com/prevAll/">.prevAll()</a> method.</p>
</div>
<h3>Examples:</h3>
<div class="entry-examples" id="entry-examples">
<div id="example-0">
<h4>Example: <span class="desc">Find the very previous sibling of each div.</span>
</h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<style>
div { width:40px; height:40px; margin:10px;
float:left; border:2px blue solid;
padding:2px; }
span { font-size:14px; }
p { clear:left; margin:10px; }
</style>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<div></div>
<div></div>
<div><span>has child</span></div>
<div></div>
<div></div>
<div></div>
<div id="start"></div>
<div></div>
<p><button>Go to Prev</button></p>
<script>
var $curr = $("#start");
$curr.css("background", "#f99");
$("button").click(function () {
$curr = $curr.prev();
$("div").css("background", "");
$curr.css("background", "#f99");
});
</script>
</body>
</html></code></pre>
<h4>Demo:</h4>
<div class="demo code-demo"></div>
</div>
<div id="example-1">
<h4>Example: <span class="desc">For each paragraph, find the very previous sibling that has a class "selected".</span>
</h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<div><span>Hello</span></div>
<p class="selected">Hello Again</p>
<p>And Again</p>
<script>$("p").prev(".selected").css("background", "yellow");</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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