101 lines
3.1 KiB
Markdown
101 lines
3.1 KiB
Markdown
---
|
|
id: bad87fee1348bd9aedd08835
|
|
title: 给单选按钮和复选框添加默认选中项
|
|
challengeType: 0
|
|
videoUrl: 'https://scrimba.com/p/pVMPUv/cWk3Qh6'
|
|
forumTopicId: 301094
|
|
dashedName: check-radio-buttons-and-checkboxes-by-default
|
|
---
|
|
|
|
# --description--
|
|
|
|
如果想设置某个单选按钮或多选按钮默认被选中，只需给 `input` 元素添加 "checked" 属性。 例如:
|
|
|
|
`<input type="radio" name="test-name" checked>`
|
|
|
|
# --instructions--
|
|
|
|
把第一个 `radio button` 和第一个 `checkbox` 都设置为默认选中。
|
|
|
|
# --hints--
|
|
|
|
表单的第一个单选按钮应被默认选中。
|
|
|
|
```js
|
|
assert($('input[type="radio"]').prop('checked'));
|
|
```
|
|
|
|
表单的第一个多选按钮应被默认选中。
|
|
|
|
```js
|
|
assert($('input[type="checkbox"]').prop('checked'));
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --seed-contents--
|
|
|
|
```html
|
|
<h2>CatPhotoApp</h2>
|
|
<main>
|
|
<p>Click here to view more <a href="#">cat photos</a>.</p>
|
|
|
|
<a href="#"><img src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
|
|
|
|
<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>
|
|
<form action="https://freecatphotoapp.com/submit-cat-photo">
|
|
<label for="indoor"><input id="indoor" type="radio" name="indoor-outdoor" value="indoor"> Indoor</label>
|
|
<label for="outdoor"><input id="outdoor" type="radio" name="indoor-outdoor" value="outdoor"> Outdoor</label><br>
|
|
<label for="loving"><input id="loving" type="checkbox" name="personality" value="loving"> Loving</label>
|
|
<label for="lazy"><input id="lazy" type="checkbox" name="personality" value="lazy"> Lazy</label>
|
|
<label for="energetic"><input id="energetic" type="checkbox" name="personality" value="energetic"> Energetic</label><br>
|
|
<input type="text" placeholder="cat photo URL" required>
|
|
<button type="submit">Submit</button>
|
|
</form>
|
|
</main>
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```html
|
|
<h2>CatPhotoApp</h2>
|
|
<main>
|
|
<p>Click here to view more <a href="#">cat photos</a>.</p>
|
|
|
|
<a href="#"><img src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
|
|
|
|
<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>
|
|
<form action="https://freecatphotoapp.com/submit-cat-photo">
|
|
<label for="indoor"><input id="indoor" type="radio" name="indoor-outdoor" value="indoor" checked> Indoor</label>
|
|
<label for="outdoor"><input id="outdoor" type="radio" name="indoor-outdoor" value="outdoor"> Outdoor</label><br>
|
|
<label for="loving"><input id="loving" type="checkbox" name="personality" value="loving" checked> Loving</label>
|
|
<label for="lazy"><input id="lazy" type="checkbox" name="personality" value="lazy"> Lazy</label>
|
|
<label for="energetic"><input id="energetic" type="checkbox" name="personality" value="energetic"> Energetic</label><br>
|
|
<input type="text" placeholder="cat photo URL" required>
|
|
<button type="submit">Submit</button>
|
|
</form>
|
|
</main>
|
|
```
|