68 lines
1.7 KiB
Markdown
68 lines
1.7 KiB
Markdown
---
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id: bd7123c9c451eddfaeb5bdef
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title: Use Bracket Notation to Find the Last Character in a String
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challengeType: 1
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videoUrl: ''
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localeTitle: 使用括号表示法查找字符串中的最后一个字符
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---
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## Description
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<section id="description">为了获得字符串的最后一个字母，您可以从字符串的长度中减去一个字母。例如，如果<code>var firstName = "Charles"</code> ，则可以使用<code>firstName[firstName.length - 1]</code>获取字符串最后一个字母的值。 </section>
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## Instructions
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<section id="instructions">使用<dfn>括号表示法</dfn>查找<code>lastName</code>变量中的最后一个字符。 <strong>暗示</strong> <br>如果卡住了，请尝试查看<code>lastLetterOfFirstName</code>变量声明。 </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>lastLetterOfLastName</code>应为“e”。
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testString: 'assert(lastLetterOfLastName === "e", "<code>lastLetterOfLastName</code> should be "e".");'
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- text: 你必须使用<code>.length</code>来获取最后一个字母。
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testString: 'assert(code.match(/\.length/g).length === 2, "You have to use <code>.length</code> to get the last letter.");'
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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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// Example
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var firstName = "Ada";
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var lastLetterOfFirstName = firstName[firstName.length - 1];
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// Setup
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var lastName = "Lovelace";
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// Only change code below this line.
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var lastLetterOfLastName = lastName;
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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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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