68 lines
2.1 KiB
Markdown
68 lines
2.1 KiB
Markdown
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---
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id: 567af2437cbaa8c51670a16c
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title: Testing Objects for Properties
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challengeType: 1
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videoUrl: ''
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localeTitle: 测试属性的对象
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---
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## Description
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<section id="description">有时检查给定对象的属性是否存在是有用的。我们可以使用对象的<code>.hasOwnProperty(propname)</code>方法来确定该对象是否具有给定的属性名称。 <code>.hasOwnProperty()</code>如果找到属性则返回<code>true</code>或<code>false</code> 。 <strong>例</strong> <blockquote> var myObj = { <br>顶部：“帽子”， <br>底部：“裤子” <br> }; <br> myObj.hasOwnProperty（ “顶部”）; //真的<br> myObj.hasOwnProperty（ “中间”）; //假</blockquote></section>
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## Instructions
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<section id="instructions">修改函数<code>checkObj</code>以测试<code>myObj</code>的<code>checkProp</code> 。如果找到该属性，则返回该属性的值。如果没有，请返回<code>"Not Found"</code> 。 </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>checkObj("gift")</code>应该返回<code>"pony"</code> 。
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testString: 'assert(checkObj("gift") === "pony", "<code>checkObj("gift")</code> should return <code>"pony"</code>.");'
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- text: <code>checkObj("pet")</code>应该返回<code>"kitten"</code> 。
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testString: 'assert(checkObj("pet") === "kitten", "<code>checkObj("pet")</code> should return <code>"kitten"</code>.");'
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- text: <code>checkObj("house")</code>应该返回<code>"Not Found"</code> 。
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testString: 'assert(checkObj("house") === "Not Found", "<code>checkObj("house")</code> should return <code>"Not Found"</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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// Setup
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var myObj = {
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gift: "pony",
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pet: "kitten",
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bed: "sleigh"
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};
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function checkObj(checkProp) {
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// Your Code Here
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return "Change Me!";
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}
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// Test your code by modifying these values
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checkObj("gift");
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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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