65 lines
2.4 KiB
Markdown
65 lines
2.4 KiB
Markdown
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---
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id: 587d7b7c367417b2b2512b1b
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title: Use the delete Keyword to Remove Object Properties
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challengeType: 1
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videoUrl: ''
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localeTitle: 使用删除关键字删除对象属性
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---
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## Description
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<section id="description">现在你知道了什么是对象及其基本特征和优点。简而言之，它们是键值存储，它提供了一种灵活，直观的数据结构方式， <strong><em>并且</em></strong>它们提供了非常快速的查找时间。在其余的挑战中，我们将描述您可以对对象执行的几个常见操作，以便您可以轻松地在程序中应用这些有用的数据结构。在早期的挑战中，我们都添加并修改了对象的键值对。在这里，我们将看到如何从对象中<em>删除</em>键值对。让我们最后一次重新审视我们的<code>foods</code>对象示例。如果我们想删除<code>apples</code>键，我们可以使用<code>delete</code>关键字删除它，如下所示： <blockquote>删除foods.apples; </blockquote></section>
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## Instructions
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<section id="instructions">使用delete关键字从<code>foods</code>对象中删除<code>oranges</code> ， <code>plums</code>和<code>strawberries</code>键。 </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>foods</code>对象只有三个键： <code>apples</code> ， <code>grapes</code>和<code>bananas</code>
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testString: 'assert(!foods.hasOwnProperty("oranges") && !foods.hasOwnProperty("plums") && !foods.hasOwnProperty("strawberries") && Object.keys(foods).length === 3, "The <code>foods</code> object only has three keys: <code>apples</code>, <code>grapes</code>, and <code>bananas</code>");'
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- text: 使用<code>delete</code> <code>oranges</code> ， <code>plums</code>和<code>strawberries</code>键
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testString: 'assert(code.search(/oranges:/) !== -1 && code.search(/plums:/) !== -1 && code.search(/strawberries:/) !== -1, "The <code>oranges</code>, <code>plums</code>, and <code>strawberries</code> keys are removed using <code>delete</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 foods = {
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apples: 25,
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oranges: 32,
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plums: 28,
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bananas: 13,
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grapes: 35,
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strawberries: 27
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};
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// change code below this line
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// change code above this line
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console.log(foods);
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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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