58 lines
1.4 KiB
Markdown
58 lines
1.4 KiB
Markdown
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---
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id: 587d8255367417b2b2512c72
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title: Use .has and .size on an ES6 Set
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challengeType: 1
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videoUrl: ''
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localeTitle: 在ES6集上使用.has和.size
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---
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## Description
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<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>
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## Instructions
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<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>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: '<code>checkSet([4, 5, 6], 3)</code>应该返回[false，3]'
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testString: 'assert(function(){var test = checkSet([4,5,6], 3); test === [ false, 3 ]}, "<code>checkSet([4, 5, 6], 3)</code> should return [ false, 3 ]");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function checkSet(arrToBeSet, checkValue){
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// change code below this line
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// change code above this line
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}
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checkSet([ 1, 2, 3], 2); // Should return [ true, 3 ]
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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