94 lines
3.4 KiB
Markdown
94 lines
3.4 KiB
Markdown
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---
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id: bad87fee1348bd9aed108826
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title: Target a Specific Child of an Element Using jQuery
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required:
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- link: 'https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.2.0/animate.css'
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challengeType: 6
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videoUrl: ''
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localeTitle: 使用jQuery定位元素的特定子元素
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---
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## Description
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<section id="description">您已经了解了为什么id属性对于使用jQuery选择器进行定位非常方便。但是你不会总是有这么整洁的ids。幸运的是，jQuery还有一些其他技巧可用于定位正确的元素。 jQuery使用CSS选择器来定位元素。 <code>target:nth-child(n)</code> CSS选择器允许您选择具有目标类或元素类型的所有第n个元素。以下是如何给每个井中的第三个元素提供反弹类： <code>$(".target:nth-child(3)").addClass("animated bounce");</code>让每个井元素中的第二个孩子反弹。您必须选择具有<code>target</code>类的元素子项。 </section>
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>target</code>元素中的第二个元素应该反弹。
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testString: 'assert($(".target:nth-child(2)").hasClass("animated") && $(".target:nth-child(2)").hasClass("bounce"), "The second element in your <code>target</code> elements should bounce.");'
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- text: 只有两个元素应该反弹。
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testString: 'assert($(".animated.bounce").length === 2, "Only two elements should bounce.");'
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- text: '您应该使用<code>:nth-child()</code>选择器来修改这些元素。'
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testString: 'assert(code.match(/\:nth-child\(/g), "You should use the <code>:nth-child()</code> selector to modify these elements.");'
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- text: 只使用jQuery将这些类添加到元素中。
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testString: 'assert(code.match(/\$\(".target:nth-child\(2\)"\)/g) || code.match(/\$\(".target:nth-child\(2\)"\)/g) || code.match(/\$\(".target"\).filter\(":nth-child\(2\)"\)/g) || code.match(/\$\(".target"\).filter\(":nth-child\(2\)"\)/g), "Only use jQuery to add these classes to the element.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='html-seed'>
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```html
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<script>
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$(document).ready(function() {
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$("#target1").css("color", "red");
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$("#target1").prop("disabled", true);
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$("#target4").remove();
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$("#target2").appendTo("#right-well");
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$("#target5").clone().appendTo("#left-well");
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$("#target1").parent().css("background-color", "red");
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$("#right-well").children().css("color", "orange");
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});
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</script>
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<!-- Only change code above this line. -->
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<div class="container-fluid">
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<h3 class="text-primary text-center">jQuery Playground</h3>
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<div class="row">
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<div class="col-xs-6">
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<h4>#left-well</h4>
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<div class="well" id="left-well">
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<button class="btn btn-default target" id="target1">#target1</button>
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<button class="btn btn-default target" id="target2">#target2</button>
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<button class="btn btn-default target" id="target3">#target3</button>
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</div>
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</div>
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<div class="col-xs-6">
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<h4>#right-well</h4>
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<div class="well" id="right-well">
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<button class="btn btn-default target" id="target4">#target4</button>
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<button class="btn btn-default target" id="target5">#target5</button>
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<button class="btn btn-default target" id="target6">#target6</button>
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</div>
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</div>
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</div>
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</div>
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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