.find()
.find( selector ) Returns: jQuery
Description: Get the descendants of each element in the current set of matched elements, filtered by a selector, jQuery object, or element.
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version added: 1.0.find( selector )
selectorA string containing a selector expression to match elements against.
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version added: 1.6.find( jQuery object )
jQuery objectA jQuery object to match elements against.
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version added: 1.6.find( element )
elementAn element to match elements against.
Given a jQuery object that represents a set of DOM elements, the .find() method allows us to search through the descendants of these elements in the DOM tree and construct a new jQuery object from the matching elements. The .find() and .children() methods are similar, except that the latter only travels a single level down the DOM tree.
The first signature for the .find()method accepts a selector expression of the same type that we can pass to the $() function. The elements will be filtered by testing whether they match this selector.
Consider a page with a basic nested list on it:
<ul class="level-1">
<li class="item-i">I</li>
<li class="item-ii">II
<ul class="level-2">
<li class="item-a">A</li>
<li class="item-b">B
<ul class="level-3">
<li class="item-1">1</li>
<li class="item-2">2</li>
<li class="item-3">3</li>
</ul>
</li>
<li class="item-c">C</li>
</ul>
</li>
<li class="item-iii">III</li>
</ul>
If we begin at item II, we can find list items within it:
$('li.item-ii').find('li').css('background-color', 'red');
The result of this call is a red background on items A, B, 1, 2, 3, and C. Even though item II matches the selector expression, it is not included in the results; only descendants are considered candidates for the match.
Unlike in the rest of the tree traversal methods, the selector expression is required in a call to
.find(). If we need to retrieve all of the descendant elements, we can pass in the universal selector'*'to accomplish this.
Selector context is implemented with the .find() method; therefore, $('li.item-ii').find('li') is equivalent to $('li', 'li.item-ii').
As of jQuery 1.6, we can also filter the selection with a given jQuery collection or element. With the same nested list as above, if we start with:
var $allListElements = $('li');
And then pass this jQuery object to find:
$('li.item-ii').find( $allListElements );
This will return a jQuery collection which contains only the list elements that are descendants of item II.
Similarly, an element may also be passed to find:
var item1 = $('li.item-1')[0];
$('li.item-ii').find( item1 ).css('background-color', 'red');
The result of this call would be a red background on item 1.
Examples:
Example: Starts with all paragraphs and searches for descendant span elements, same as $("p span")
<!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p><span>Hello</span>, how are you?</p>
<p>Me? I'm <span>good</span>.</p>
<script>
$("p").find("span").css('color','red');
</script>
</body>
</html>Demo:
Example: A selection using a jQuery collection of all span tags. Only spans within p tags are changed to red while others are left blue.
<!DOCTYPE html>
<html>
<head>
<style>
span { color: blue; }
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p><span>Hello</span>, how are you?</p>
<p>Me? I'm <span>good</span>.</p>
<div>Did you <span>eat</span> yet?</div>
<script>
var $spans = $('span');
$("p").find( $spans ).css('color','red');
</script>
</body>
</html>Demo:
Example: Add spans around each word then add a hover and italicize words with the letter t.
<!DOCTYPE html>
<html>
<head>
<style>
p { font-size:20px; width:200px; cursor:default;
color:blue; font-weight:bold; margin:0 10px; }
.hilite { background:yellow; }
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p>
When the day is short
find that which matters to you
or stop believing
</p>
<script>
var newText = $("p").text().split(" ").join("</span> <span>");
newText = "<span>" + newText + "</span>";
$("p").html( newText )
.find('span')
.hover(function() {
$(this).addClass("hilite");
},
function() { $(this).removeClass("hilite");
})
.end()
.find(":contains('t')")
.css({"font-style":"italic", "font-weight":"bolder"});
</script>
</body>
</html>