80 lines
3.2 KiB
Markdown
80 lines
3.2 KiB
Markdown
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---
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id: 587d7b7d367417b2b2512b1f
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title: Modify an Array Stored in an Object
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challengeType: 1
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videoUrl: ''
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localeTitle: 修改存储在对象中的数组
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---
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## Description
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<section id="description">现在您已经看到了JavaScript对象的所有基本操作。您可以添加，修改和删除键值对，检查键是否存在，并迭代对象中的所有键。随着您继续学习JavaScript，您将看到更多功能的对象应用程序。此外，课程后面的可选高级数据结构课程还涵盖ES6 <dfn>Map</dfn>和<dfn>Set</dfn>对象，这两个对象与普通对象类似，但提供了一些附加功能。既然您已经学习了数组和对象的基础知识，那么您已经准备好开始使用JavaScript解决更复杂的问题了！ </section>
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## Instructions
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<section id="instructions">看看我们在代码编辑器中提供的对象。 <code>user</code>对象包含三个键。 <code>data</code>键包含五个键，其中一个键包含一组<code>friends</code> 。从这里，您可以看到灵活的对象如何作为数据结构。我们已经开始编写一个函数<code>addFriend</code> 。完成编写它以便它获取<code>user</code>对象并将<code>friend</code>参数的名称添加到存储在<code>user.data.friends</code>中的数组并返回该数组。 </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>user</code>对象具有<code>name</code> ， <code>age</code>和<code>data</code>键
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testString: 'assert("name" in user && "age" in user && "data" in user, "The <code>user</code> object has <code>name</code>, <code>age</code>, and <code>data</code> keys");'
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- text: <code>addFriend</code>函数接受<code>user</code>对象和<code>friend</code>字符串作为参数，并将朋友添加到<code>user</code>对象中的<code>friends</code>数组
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testString: 'assert((function() { let L1 = user.data.friends.length; addFriend(user, "Sean"); let L2 = user.data.friends.length; return (L2 === L1 + 1); })(), "The <code>addFriend</code> function accepts a <code>user</code> object and a <code>friend</code> string as arguments and adds the friend to the array of <code>friends</code> in the <code>user</code> object");'
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- text: '<code>addFriend(user, "Pete")</code>应该返回<code>["Sam", "Kira", "Tomo", "Pete"]</code>'
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testString: 'assert.deepEqual((function() { delete user.data.friends; user.data.friends = ["Sam", "Kira", "Tomo"]; return addFriend(user, "Pete") })(), ["Sam", "Kira", "Tomo", "Pete"], "<code>addFriend(user, "Pete")</code> should return <code>["Sam", "Kira", "Tomo", "Pete"]</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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let user = {
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name: 'Kenneth',
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age: 28,
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data: {
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username: 'kennethCodesAllDay',
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joinDate: 'March 26, 2016',
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organization: 'freeCodeCamp',
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friends: [
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'Sam',
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'Kira',
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'Tomo'
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],
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location: {
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city: 'San Francisco',
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state: 'CA',
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country: 'USA'
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}
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}
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};
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function addFriend(userObj, friend) {
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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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console.log(addFriend(user, 'Pete'));
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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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