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											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
										 |  |  | title: 匹配空白字符 | 
					
						
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											2018-10-10 18:03:03 -04:00
										 |  |  | challengeType: 1 | 
					
						
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										 |  |  | forumTopicId: 301359 | 
					
						
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											2021-01-13 03:31:00 +01:00
										 |  |  | dashedName: match-whitespace | 
					
						
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											2018-10-10 18:03:03 -04:00
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											2020-12-16 00:37:30 -07:00
										 |  |  | # --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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										 |  |  | 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 | 
					
						
							|  |  |  | let whiteSpace = "Whitespace. Whitespace everywhere!" | 
					
						
							|  |  |  | let spaceRegex = /\s/g; | 
					
						
							|  |  |  | whiteSpace.match(spaceRegex); | 
					
						
							|  |  |  | ``` | 
					
						
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										 |  |  | 这个 `match` 调用将返回 `[" ", " "]`。 | 
					
						
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											2020-12-16 00:37:30 -07:00
										 |  |  | # --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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											2018-10-10 18:03:03 -04:00
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											2021-03-14 21:20:39 -06:00
										 |  |  | 你的正则表达式应该使用全局标识。 | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert(countWhiteSpace.global); | 
					
						
							|  |  |  | ``` | 
					
						
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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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											2018-10-10 18:03:03 -04:00
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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 | 
					
						
							|  |  |  | assert( | 
					
						
							|  |  |  |   'Men are from Mars and women are from Venus.'.match(countWhiteSpace).length == | 
					
						
							|  |  |  |     8 | 
					
						
							|  |  |  | ); | 
					
						
							|  |  |  | ``` | 
					
						
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											2018-10-10 18:03:03 -04:00
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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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											2018-10-10 18:03:03 -04:00
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										 |  |  | ```js | 
					
						
							|  |  |  | assert('Space: the final frontier.'.match(countWhiteSpace).length == 3); | 
					
						
							|  |  |  | ``` | 
					
						
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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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											2018-10-10 18:03:03 -04:00
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							|  |  |  | ```js | 
					
						
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										 |  |  | assert('MindYourPersonalSpace'.match(countWhiteSpace) == null); | 
					
						
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										 |  |  | ``` | 
					
						
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											2021-01-13 03:31:00 +01:00
										 |  |  | # --seed--
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							|  |  |  | ## --seed-contents--
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							|  |  |  | ```js | 
					
						
							|  |  |  | let sample = "Whitespace is important in separating words"; | 
					
						
							|  |  |  | let countWhiteSpace = /change/; // Change this line | 
					
						
							|  |  |  | let result = sample.match(countWhiteSpace); | 
					
						
							|  |  |  | ``` | 
					
						
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											2020-12-16 00:37:30 -07:00
										 |  |  | # --solutions--
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										 |  |  | ```js | 
					
						
							|  |  |  | let sample = "Whitespace is important in separating words"; | 
					
						
							|  |  |  | let countWhiteSpace = /\s/g; | 
					
						
							|  |  |  | let result = sample.match(countWhiteSpace); | 
					
						
							|  |  |  | ``` |