53 lines
1.7 KiB
Markdown
53 lines
1.7 KiB
Markdown
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---
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id: 587d825b367417b2b2512c8d
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title: Create an ES6 JavaScript Map
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challengeType: 1
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videoUrl: ''
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localeTitle: 创建ES6 JavaScript地图
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---
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## Description
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<section id="description">新版本的JavaScript为我们提供了一个内置的Map对象，它提供了我们在上一次挑战中手工编写的大部分功能。此Map对象虽然与常规JavaScript对象类似，但它提供了一些普通对象缺少的有用功能。例如，ES6 Map跟踪添加到其中的项目的插入顺序。以下是其方法的更完整概述： <code>.has(key)</code>基于键的存在返回true或false <code>.get(key)</code>返回与键相关联的值<code>.set(key, value)</code>设置新键，值对<code>.delete(key)</code>删除一个键，值对<code>.clear()</code>删除所有键值对<code>.entries()</code>以插入顺序返回所有键的数组<code>.values()</code>返回插入中所有值的数组order说明：定义一个JavaScript Map对象并为其分配一个名为myMap的变量。添加密钥，值对<code>freeCodeCamp</code> ， <code>Awesome!</code>它。 </section>
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## Instructions
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<section id="instructions">
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</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: myMap对象存在。
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testString: 'assert(typeof myMap === "object", "The myMap object exists.");'
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- text: myMap包含键值对<code>freeCodeCamp</code> ， <code>Awesome!</code> 。
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testString: 'assert(myMap.get("freeCodeCamp") === "Awesome!", "myMap contains the key value pair <code>freeCodeCamp</code>, <code>Awesome!</code>.");'
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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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// change code below this line
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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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