freeCodeCamp/curriculum/challenges/chinese/01-responsive-web-design/basic-html-and-html5/link-to-internal-sections-of-a-page-with-anchor-elements.md

---
id: bad88fee1348bd9aedf08816
title: 用 a 实现网页内部跳转
challengeType: 0
videoUrl: 'https://scrimba.com/p/pVMPUv/cyrDRUL'
forumTopicId: 301098
dashedName: link-to-internal-sections-of-a-page-with-anchor-elements
---

# --description--

`a` 元素还可以用来实现页面内不同区域的跳转，只需要把 `a` 元素的 `href` 值设置为井号 `#` 加欲跳转区域所对应的 `id` 属性值即可。`id` 是描述网页元素的一个属性，它的值在整个页面中唯一。

下面是用来创建内部 `a` 的例子：

```html
<a href="#contacts-header">Contacts</a>
...
<h2 id="contacts-header">Contacts</h2>
```

当用户点击了 `Contacts` 链接，页面就会跳转到网页的 **Contacts** 区域。

# --instructions--

请修改 `href` 属性值为 `#footer` 来将外部链接更改为内部链接，同时修改文本 `cat photos` 为 `Jump to Bottom`。

移除 `target="\_blank"` 属性，这个属性的存在会让链接在新标签页中打开。

然后添加一个 `<footer>` 元素，并将它的 `id` 属性值设置为 `footer`。

# --hints--

页面中应只存在一个 `a` 元素。

```js
assert($('a').length == 1);
```

页面中应只存在一个 `footer` 元素。

```js
assert($('footer').length == 1);
```

`a` 的 `href` 属性值应为 `#footer`。

```js
assert($('a').eq(0).attr('href') == '#footer');
```

`a` 不应有 `target` 属性。

```js
assert(
  typeof $('a').eq(0).attr('target') == typeof undefined ||
    $('a').eq(0).attr('target') == true
);
```

`a` 的内容文本应为 `Jump to Bottom`。

```js
assert(
  $('a')
    .eq(0)
    .text()
    .match(/Jump to Bottom/gi)
);
```

`footer` 元素的 `id` 属性值应为 `footer`。

```js
assert($('footer').eq(0).attr('id') == 'footer');
```

# --seed--

## --seed-contents--

```html
<h2>CatPhotoApp</h2>
<main>

  <a href="https://freecatphotoapp.com" target="_blank">cat photos</a>

  <img src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back.">

  <p>Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff. Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched. Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff.</p>
  <p>Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched. Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff. Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched.</p>
  <p>Meowwww loved it, hated it, loved it, hated it yet spill litter box, scratch at owner, destroy all furniture, especially couch or lay on arms while you're using the keyboard. Missing until dinner time toy mouse squeak roll over. With tail in the air lounge in doorway. Man running from cops stops to pet cats, goes to jail.</p>
  <p>Intently stare at the same spot poop in the plant pot but kitten is playing with dead mouse. Get video posted to internet for chasing red dot leave fur on owners clothes meow to be let out and mesmerizing birds leave fur on owners clothes or favor packaging over toy so purr for no reason. Meow to be let out play time intently sniff hand run outside as soon as door open yet destroy couch.</p>

</main>

<footer>Copyright Cat Photo App</footer>
```

# --solutions--

```html
<h2>CatPhotoApp</h2>
<main>

  <a href="#footer">Jump to Bottom</a>

  <img src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back.">

  <p>Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff. Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched. Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff.</p>
  <p>Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched. Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff. Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched.</p>
  <p>Meowwww loved it, hated it, loved it, hated it yet spill litter box, scratch at owner, destroy all furniture, especially couch or lay on arms while you're using the keyboard. Missing until dinner time toy mouse squeak roll over. With tail in the air lounge in doorway. Man running from cops stops to pet cats, goes to jail.</p>
  <p>Intently stare at the same spot poop in the plant pot but kitten is playing with dead mouse. Get video posted to internet for chasing red dot leave fur on owners clothes meow to be let out and mesmerizing birds leave fur on owners clothes or favor packaging over toy so purr for no reason. Meow to be let out play time intently sniff hand run outside as soon as door open yet destroy couch.</p>

</main>

<footer id="footer">Copyright Cat Photo App</footer>
```