58 lines
1.4 KiB
Markdown
58 lines
1.4 KiB
Markdown
|
---
|
|||
|
id: 587d8255367417b2b2512c72
|
|||
|
title: Use .has and .size on an ES6 Set
|
|||
|
challengeType: 1
|
|||
|
videoUrl: ''
|
|||
|
localeTitle: 在ES6集上使用.has和.size
|
|||
|
---
|
|||
|
|
|||
|
## Description
|
|||
|
<section id="description">让我们看一下ES6 Set对象上可用的.has和.size方法。首先,创建一个ES6 Set <code>var set = new Set([1,2,3]);</code> .has方法将检查该值是否包含在集合中。 <code>var hasTwo = set.has(2);</code> .size方法将返回一个表示Set <code>var howBig = set.size;</code>大小的整数<code>var howBig = set.size;</code> </section>
|
|||
|
|
|||
|
## Instructions
|
|||
|
<section id="instructions">在本练习中,我们将数组和值传递给checkSet()函数。您的函数应该从数组参数创建ES6集。查找该集是否包含value参数。找到集合的大小。并在数组中返回这两个值。 </section>
|
|||
|
|
|||
|
## Tests
|
|||
|
<section id='tests'>
|
|||
|
|
|||
|
```yml
|
|||
|
tests:
|
|||
|
- text: '<code>checkSet([4, 5, 6], 3)</code>应该返回[false,3]'
|
|||
|
testString: 'assert(function(){var test = checkSet([4,5,6], 3); test === [ false, 3 ]}, "<code>checkSet([4, 5, 6], 3)</code> should return [ false, 3 ]");'
|
|||
|
|
|||
|
```
|
|||
|
|
|||
|
</section>
|
|||
|
|
|||
|
## Challenge Seed
|
|||
|
<section id='challengeSeed'>
|
|||
|
|
|||
|
<div id='js-seed'>
|
|||
|
|
|||
|
```js
|
|||
|
function checkSet(arrToBeSet, checkValue){
|
|||
|
|
|||
|
// change code below this line
|
|||
|
|
|||
|
// change code above this line
|
|||
|
|
|||
|
}
|
|||
|
|
|||
|
checkSet([ 1, 2, 3], 2); // Should return [ true, 3 ]
|
|||
|
|
|||
|
```
|
|||
|
|
|||
|
</div>
|
|||
|
|
|||
|
|
|||
|
|
|||
|
</section>
|
|||
|
|
|||
|
## Solution
|
|||
|
<section id='solution'>
|
|||
|
|
|||
|
```js
|
|||
|
// solution required
|
|||
|
```
|
|||
|
</section>
|