78 lines
1.8 KiB
Markdown
78 lines
1.8 KiB
Markdown
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---
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id: 587d7db8367417b2b2512ba3
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title: 匹配空白字符
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challengeType: 1
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forumTopicId: 301359
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dashedName: match-whitespace
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---
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# --description--
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迄今爲止的挑戰包括匹配字母和數字。 還可以匹配字符之間的空格。
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可以使用 `\s` 搜尋空格，其中 `s` 是小寫。 此匹配模式將匹配空格、回車符、製表符、換頁符和換行符。 可以認爲這類似於元字符 `[ \r\t\f\n\v]`。
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```js
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let whiteSpace = "Whitespace. Whitespace everywhere!"
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let spaceRegex = /\s/g;
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whiteSpace.match(spaceRegex);
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```
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這個 `match` 調用將返回 `[" ", " "]`。
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# --instructions--
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修改正則表達式 `countWhiteSpace` 查找字符串中的多個空白字符。
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# --hints--
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你的正則表達式應該使用全局標識。
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```js
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assert(countWhiteSpace.global);
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```
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正則表達式應該使用元字符 `\s` 匹配所有的空白。
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```js
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assert(/\\s/.test(countWhiteSpace.source));
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```
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你的正則表達式應該在字符串 `Men are from Mars and women are from Venus.` 中找到 8 個非空格字符。
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```js
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assert(
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'Men are from Mars and women are from Venus.'.match(countWhiteSpace).length ==
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8
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);
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```
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你的正則表達式應該在 `Space: the final frontier.` 中匹配到 3 個非空白字符。
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```js
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assert('Space: the final frontier.'.match(countWhiteSpace).length == 3);
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```
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你的正則表達式在 `MindYourPersonalSpace` 中應該匹配不到空白字符。
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```js
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assert('MindYourPersonalSpace'.match(countWhiteSpace) == null);
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```
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# --seed--
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## --seed-contents--
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```js
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let sample = "Whitespace is important in separating words";
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let countWhiteSpace = /change/; // Change this line
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let result = sample.match(countWhiteSpace);
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```
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# --solutions--
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```js
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let sample = "Whitespace is important in separating words";
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let countWhiteSpace = /\s/g;
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let result = sample.match(countWhiteSpace);
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```
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