62 lines
3.6 KiB
Markdown
62 lines
3.6 KiB
Markdown
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---
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id: 587d7db7367417b2b2512b9f
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title: Match All Letters and Numbers
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challengeType: 1
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videoUrl: ''
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localeTitle: 匹配所有字母和数字
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---
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## Description
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<section id="description">使用字符类，您可以使用<code>[az]</code>搜索字母表中的所有字母。这种字符类很常见，它有一个快捷方式，虽然它还包含一些额外的字符。 JavaScript中与字母表匹配的最接近的字符类是<code>\w</code> 。此快捷方式等于<code>[A-Za-z0-9_]</code> 。此字符类匹配大写和小写字母加数字。注意，此字符类还包括下划线字符（ <code>_</code> ）。 <blockquote>让longHand = / [A-Za-z0-9 _] + /; <br>让shortHand = / \ w + /; <br>让数字=“42”; <br> let varNames =“important_var”; <br> longHand.test（数字）; //返回true <br> shortHand.test（数字）; //返回true <br> longHand.test（varNames）; //返回true <br> shortHand.test（varNames）; //返回true </blockquote>这些快捷方式字符类也称为<code>shorthand character classes</code> 。 </section>
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## Instructions
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<section id="instructions">使用速记字符类<code>\w</code>来计算各种引号和字符串中的字母数字字符数。 </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: 你的正则表达式应该使用全局标志。
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testString: 'assert(alphabetRegexV2.global, "Your regex should use the global flag.");'
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- text: 你的正则表达式应该使用速记字符
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testString: 'assert(/\\w/.test(alphabetRegexV2.source), "Your regex should use the shorthand character <code>\w</code> to match all characters which are alphanumeric.");'
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- text: 你的正则表达式应该在<code>"The five boxing wizards jump quickly."</code>找到31个字母数字字符<code>"The five boxing wizards jump quickly."</code>
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testString: 'assert("The five boxing wizards jump quickly.".match(alphabetRegexV2).length === 31, "Your regex should find 31 alphanumeric characters in <code>"The five boxing wizards jump quickly."</code>");'
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- text: 你的正则表达式应该在<code>"Pack my box with five dozen liquor jugs."</code>找到32个字母数字字符<code>"Pack my box with five dozen liquor jugs."</code>
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testString: 'assert("Pack my box with five dozen liquor jugs.".match(alphabetRegexV2).length === 32, "Your regex should find 32 alphanumeric characters in <code>"Pack my box with five dozen liquor jugs."</code>");'
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- text: 你的正则表达式应该在<code>"How vexingly quick daft zebras jump!"</code>找到30个字母数字字符<code>"How vexingly quick daft zebras jump!"</code>
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testString: 'assert("How vexingly quick daft zebras jump!".match(alphabetRegexV2).length === 30, "Your regex should find 30 alphanumeric characters in <code>"How vexingly quick daft zebras jump!"</code>");'
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- text: 你的正则表达式应该在<code>"123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ."</code>找到36个字母数字字符<code>"123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ."</code>
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testString: 'assert("123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ.".match(alphabetRegexV2).length === 36, "Your regex should find 36 alphanumeric characters in <code>"123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ."</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 quoteSample = "The five boxing wizards jump quickly.";
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let alphabetRegexV2 = /change/; // Change this line
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let result = quoteSample.match(alphabetRegexV2).length;
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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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