---
id: bad87fee1348bd9aedd08845
title: 在按钮中添加字体图标
challengeType: 0
forumTopicId: 16638
required:
  - 
    link: 'https://use.fontawesome.com/releases/v5.8.1/css/all.css'
    raw: true
dashedName: add-font-awesome-icons-to-our-buttons
---

# --description--

Font Awesome 是一个非常便利的图标库。 这些图标可以是网络字体，也可以是一张矢量图。 这些图标就和字体一样， 不仅能通过像素单位指定它们的大小，它们也同样会继承父级 HTML 元素的字体大小。

可以将 Font Awesome 图标库添加至任何一个 web app 中，方法很简单，只需要在 HTML 头部增加下列代码即可：

`<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.8.1/css/all.css" integrity="sha384-50oBUHEmvpQ+1lW4y57PTFmhCaXp0ML5d60M1M7uH2+nqUivzIebhndOJK28anvf" crossorigin="anonymous">`

不过在这里，已经预先为此页面添加了上述代码。

`i` 元素起初用于让其它元素具有斜体（italic）的效果，不过现在一般用于显示图标。 可以把 Font Awesome 中的 class 属性添加到 `i` 元素中，让它变成一个图标，比如：

`<i class="fas fa-info-circle"></i>`

注意用 `span` 元素展示图标也是可以的。

# --instructions--

给 like 按钮添加一个 Font Awesome `thumbs-up` 图标，具体方法是给 `i` 元素添加 `fas` 和 `fa-thumbs-up` class 属性。 确保将 `Like` 文本放在图标旁边。

# --hints--

增加一个 class 为 `fas` 和 `fa-thumbs-up` 的 `i` 元素。

```js
assert($('i').is('.fas.fa-thumbs-up') || $('span').is('.fas.fa-thumbs-up'));
```

`fa-thumbs-up` 图标应该在 Like 按钮中。

```js
assert(
  ($('i.fa-thumbs-up').parent().text().match(/Like/gi) &&
    $('.btn-primary > i').is('.fas.fa-thumbs-up')) ||
    ($('span.fa-thumbs-up').parent().text().match(/Like/gi) &&
      $('.btn-primary > span').is('.fas.fa-thumbs-up'))
);
```

`i` 元素应该在 `button` 元素中。

```js
assert(
  $('button').children('i').length > 0 ||
    $('button').children('span').length > 0
);
```

确保图标元素有一个闭合标签。

```js
assert(code.match(/<\/i>|<\/span>/g));
```

# --seed--

## --seed-contents--

```html
<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>
  h2 {
    font-family: Lobster, Monospace;
  }

  .thick-green-border {
    border-color: green;
    border-width: 10px;
    border-style: solid;
    border-radius: 50%;
  }
</style>

<div class="container-fluid">
  <div class="row">
    <div class="col-xs-8">
      <h2 class="text-primary text-center">CatPhotoApp</h2>
    </div>
    <div class="col-xs-4">
      <a href="#"><img class="img-responsive thick-green-border" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
    </div>
  </div>
  <img src="https://bit.ly/fcc-running-cats" class="img-responsive" alt="Three kittens running towards the camera.">
  <div class="row">
    <div class="col-xs-4">
      <button class="btn btn-block btn-primary">Like</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-info">Info</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-danger">Delete</button>
    </div>
  </div>
  <p>Things cats <span class="text-danger">love:</span></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>
  <form action="https://freecatphotoapp.com/submit-cat-photo">
    <label><input type="radio" name="indoor-outdoor"> Indoor</label>
    <label><input type="radio" name="indoor-outdoor"> Outdoor</label>
    <label><input type="checkbox" name="personality"> Loving</label>
    <label><input type="checkbox" name="personality"> Lazy</label>
    <label><input type="checkbox" name="personality"> Crazy</label>
    <input type="text" placeholder="cat photo URL" required>
    <button type="submit">Submit</button>
  </form>
</div>
```

# --solutions--

```html
<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>
  h2 {
    font-family: Lobster, Monospace;
  }

  .thick-green-border {
    border-color: green;
    border-width: 10px;
    border-style: solid;
    border-radius: 50%;
  }
</style>

<div class="container-fluid">
  <div class="row">
    <div class="col-xs-8">
      <h2 class="text-primary text-center">CatPhotoApp</h2>
    </div>
    <div class="col-xs-4">
      <a href="#"><img class="img-responsive thick-green-border" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
    </div>
  </div>
  <img src="https://bit.ly/fcc-running-cats" class="img-responsive" alt="Three kittens running towards the camera.">
  <div class="row">
    <div class="col-xs-4">
      <button class="btn btn-block btn-primary"><i class="fas fa-thumbs-up"></i> Like</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-info">Info</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-danger">Delete</button>
    </div>
  </div>
  <p>Things cats <span class="text-danger">love:</span></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>
  <form action="https://freecatphotoapp.com/submit-cat-photo">
    <label><input type="radio" name="indoor-outdoor"> Indoor</label>
    <label><input type="radio" name="indoor-outdoor"> Outdoor</label>
    <label><input type="checkbox" name="personality"> Loving</label>
    <label><input type="checkbox" name="personality"> Lazy</label>
    <label><input type="checkbox" name="personality"> Crazy</label>
    <input type="text" placeholder="cat photo URL" required>
    <button type="submit">Submit</button>
  </form>
</div>
```