4.2 KiB
4.2 KiB
id | title | challengeType | videoUrl | forumTopicId | dashedName |
---|---|---|---|---|---|
bad87eee1348bd9aede07836 | 设置元素的 id | 0 | https://scrimba.com/c/cN6MEc2 | 18279 | set-the-id-of-an-element |
--description--
除了 class 属性,每一个 HTML 元素都有一个 id
属性。
使用 id
有几个好处:你可以通过 id
选择器来改变单个元素的样式。在稍后的课程中,你还会了解到如何在 JavaScript 里面用它来选择和操作元素。
根据规范,id
属性应是唯一的。 尽管浏览器并非必须执行这条规范,但这是广泛认可的最佳实践。 因此,请不要给多个元素设置相同的 id
。
设置 h2
元素的 id 为 cat-photo-app
的代码如下:
<h2 id="cat-photo-app">
--instructions--
设置form
元素的 id 为cat-photo-form
。
--hints--
form
元素的 id 应为 cat-photo-form
。
assert($('form').attr('id') === 'cat-photo-form');
--seed--
--seed-contents--
<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>
.red-text {
color: red;
}
h2 {
font-family: Lobster, monospace;
}
p {
font-size: 16px;
font-family: monospace;
}
.thick-green-border {
border-color: green;
border-width: 10px;
border-style: solid;
border-radius: 50%;
}
.smaller-image {
width: 100px;
}
.silver-background {
background-color: silver;
}
</style>
<h2 class="red-text">CatPhotoApp</h2>
<main>
<p class="red-text">Click here to view more <a href="#">cat photos</a>.</p>
<a href="#"><img class="smaller-image thick-green-border" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
<div class="silver-background">
<p>Things cats love:</p>
<ul>
<li>cat nip</li>
<li>laser pointers</li>
<li>lasagna</li>
</ul>
<p>Top 3 things cats hate:</p>
<ol>
<li>flea treatment</li>
<li>thunder</li>
<li>other cats</li>
</ol>
</div>
<form action="https://freecatphotoapp.com/submit-cat-photo">
<label><input type="radio" name="indoor-outdoor" checked> Indoor</label>
<label><input type="radio" name="indoor-outdoor"> Outdoor</label><br>
<label><input type="checkbox" name="personality" checked> Loving</label>
<label><input type="checkbox" name="personality"> Lazy</label>
<label><input type="checkbox" name="personality"> Energetic</label><br>
<input type="text" placeholder="cat photo URL" required>
<button type="submit">Submit</button>
</form>
</main>
--solutions--
<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>
.red-text {
color: red;
}
h2 {
font-family: Lobster, monospace;
}
p {
font-size: 16px;
font-family: monospace;
}
.thick-green-border {
border-color: green;
border-width: 10px;
border-style: solid;
border-radius: 50%;
}
.smaller-image {
width: 100px;
}
.silver-background {
background-color: silver;
}
</style>
<h2 class="red-text">CatPhotoApp</h2>
<main>
<p class="red-text">Click here to view more <a href="#">cat photos</a>.</p>
<a href="#"><img class="smaller-image thick-green-border" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
<div class="silver-background">
<p>Things cats love:</p>
<ul>
<li>cat nip</li>
<li>laser pointers</li>
<li>lasagna</li>
</ul>
<p>Top 3 things cats hate:</p>
<ol>
<li>flea treatment</li>
<li>thunder</li>
<li>other cats</li>
</ol>
</div>
<form action="https://freecatphotoapp.com/submit-cat-photo" id="cat-photo-form">
<label><input type="radio" name="indoor-outdoor" checked> Indoor</label>
<label><input type="radio" name="indoor-outdoor"> Outdoor</label><br>
<label><input type="checkbox" name="personality" checked> Loving</label>
<label><input type="checkbox" name="personality"> Lazy</label>
<label><input type="checkbox" name="personality"> Energetic</label><br>
<input type="text" placeholder="cat photo URL" required>
<button type="submit">Submit</button>
</form>
</main>