freeCodeCamp/curriculum/challenges/english/03-front-end-libraries/jquery/target-even-elements-using-...

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---
id: bad87fee1348bd9aed008826
title: Target Even Elements Using jQuery
required:
- link: 'https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.2.0/animate.css'
challengeType: 6
forumTopicId: 18318
---
## Description
<section id='description'>
You can also target elements based on their positions using <code>:odd</code> or <code>:even</code> selectors.
Note that jQuery is zero-indexed which means the first element in a selection has a position of 0. This can be a little confusing as, counter-intuitively, <code>:odd</code> selects the second element (position 1), fourth element (position 3), and so on.
Here's how you would target all the odd elements with class <code>target</code> and give them classes:
<code>$(".target:odd").addClass("animated shake");</code>
Try selecting all the even <code>target</code> elements and giving them the classes of <code>animated</code> and <code>shake</code>. Remember that <strong>even</strong> refers to the position of elements with a zero-based system in mind.
</section>
## Instructions
<section id='instructions'>
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: All of the <code>target</code> elements that jQuery considers to be even should shake.
testString: assert($('.target:even').hasClass('animated') && $('.target:even').hasClass('shake'));
- text: You should use the <code>&#58;even</code> selector to modify these elements.
testString: assert(code.match(/\:even/g));
- text: Only use jQuery to add these classes to the element.
testString: assert(code.match(/\$\(".target:even"\)/g) || code.match(/\$\('.target:even'\)/g) || code.match(/\$\(".target"\).filter\(":even"\)/g) || code.match(/\$\('.target'\).filter\(':even'\)/g));
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='html-seed'>
```html
<script>
$(document).ready(function() {
$("#target1").css("color", "red");
$("#target1").prop("disabled", true);
$("#target4").remove();
$("#target2").appendTo("#right-well");
$("#target5").clone().appendTo("#left-well");
$("#target1").parent().css("background-color", "red");
$("#right-well").children().css("color", "orange");
$("#left-well").children().css("color", "green");
$(".target:nth-child(2)").addClass("animated bounce");
});
</script>
<!-- Only change code above this line. -->
<div class="container-fluid">
<h3 class="text-primary text-center">jQuery Playground</h3>
<div class="row">
<div class="col-xs-6">
<h4>#left-well</h4>
<div class="well" id="left-well">
<button class="btn btn-default target" id="target1">#target1</button>
<button class="btn btn-default target" id="target2">#target2</button>
<button class="btn btn-default target" id="target3">#target3</button>
</div>
</div>
<div class="col-xs-6">
<h4>#right-well</h4>
<div class="well" id="right-well">
<button class="btn btn-default target" id="target4">#target4</button>
<button class="btn btn-default target" id="target5">#target5</button>
<button class="btn btn-default target" id="target6">#target6</button>
</div>
</div>
</div>
</div>
```
</div>
</section>
## Solution
<section id='solution'>
```html
<script>
$(document).ready(function() {
$("#target1").css("color", "red");
$("#target1").prop("disabled", true);
$("#target4").remove();
$("#target2").appendTo("#right-well");
$("#target5").clone().appendTo("#left-well");
$("#target1").parent().css("background-color", "red");
$("#right-well").children().css("color", "orange");
$("#left-well").children().css("color", "green");
$(".target:nth-child(2)").addClass("animated bounce");
$(".target:even").addClass("animated shake");
});
</script>
<!-- Only change code above this line. -->
<div class="container-fluid">
<h3 class="text-primary text-center">jQuery Playground</h3>
<div class="row">
<div class="col-xs-6">
<h4>#left-well</h4>
<div class="well" id="left-well">
<button class="btn btn-default target" id="target1">#target1</button>
<button class="btn btn-default target" id="target2">#target2</button>
<button class="btn btn-default target" id="target3">#target3</button>
</div>
</div>
<div class="col-xs-6">
<h4>#right-well</h4>
<div class="well" id="right-well">
<button class="btn btn-default target" id="target4">#target4</button>
<button class="btn btn-default target" id="target5">#target5</button>
<button class="btn btn-default target" id="target6">#target6</button>
</div>
</div>
</div>
</div>
```
</section>