2018-10-10 18:03:03 -04:00
										 
									 
								 
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								id: 587d7db8367417b2b2512ba3
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											2021-03-14 21:20:39 -06:00
										 
									 
								 
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								title: 匹配空白字符
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								challengeType: 1
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											2020-08-04 15:14:01 +08:00
										 
									 
								 
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								forumTopicId: 301359
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: match-whitespace
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								---
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											2020-12-16 00:37:30 -07:00
										 
									 
								 
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								# --description--
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								迄今为止的挑战包括匹配字母和数字。 还可以匹配字符之间的空格。
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											2021-03-14 21:20:39 -06:00
										 
									 
								 
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								可以使用 `\s` 搜寻空格,其中 `s` 是小写。 此匹配模式将匹配空格、回车符、制表符、换页符和换行符。 可以认为这类似于元字符 `[ \r\t\f\n\v]`。
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											2020-08-04 15:14:01 +08:00
										 
									 
								 
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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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											2021-03-14 21:20:39 -06:00
										 
									 
								 
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								这个 `match` 调用将返回 `[" ", " "]`。
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								# --instructions--
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								修改正则表达式 `countWhiteSpace` 查找字符串中的多个空白字符。
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								# --hints--
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								你的正则表达式应该使用全局标识。
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								```js
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								assert(countWhiteSpace.global);
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								```
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								正则表达式应该使用元字符 `\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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								你的正则表达式应该在字符串 `Men are from Mars and women are from Venus.` 中找到 8 个非空格字符。
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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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								你的正则表达式应该在 `Space: the final frontier.` 中匹配到 3 个非空白字符。
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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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								你的正则表达式在 `MindYourPersonalSpace` 中应该匹配不到空白字符。
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								```js
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								assert('MindYourPersonalSpace'.match(countWhiteSpace) == null);
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								```
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											2020-08-04 15:14:01 +08:00
										 
									 
								 
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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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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