58 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			58 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | |||
|  | id: 587d7dba367417b2b2512ba8 | |||
|  | title: Check for All or None | |||
|  | challengeType: 1 | |||
|  | videoUrl: '' | |||
|  | localeTitle: 检查全部或无 | |||
|  | --- | |||
|  | 
 | |||
|  | ## Description
 | |||
|  | <section id="description">有时,您要搜索的模式可能包含可能存在或可能不存在的模式。但是,尽管如此,检查它们可能很重要。您可以指定可能存在带问号的元素, <code>?</code> 。这将检查前一个元素中的零个或一个。您可以将此符号视为前一个元素是可选的。例如,美式英语和英式英语略有不同,您可以使用问号来匹配两种拼写。 <blockquote>让美国人=“颜色”; <br>让british =“color”; <br>让rainbowRegex = / colou?r /; <br> rainbowRegex.test(美国); //返回true <br> rainbowRegex.test(英国); //返回true </blockquote></section> | |||
|  | 
 | |||
|  | ## Instructions
 | |||
|  | <section id="instructions">更改正则表达式<code>favRegex</code>以匹配该单词的美国英语(收藏)和英国英语(收藏)版本。 </section> | |||
|  | 
 | |||
|  | ## Tests
 | |||
|  | <section id='tests'> | |||
|  | 
 | |||
|  | ```yml | |||
|  | tests: | |||
|  |   - text: 你的正则表达式应该使用可选的符号, <code>?</code> 。 | |||
|  |     testString: 'assert(favRegex.source.match(/\?/).length > 0, "Your regex should use the optional symbol, <code>?</code>.");' | |||
|  |   - text: 你的正则表达式应该匹配<code>"favorite"</code> | |||
|  |     testString: 'assert(favRegex.test("favorite"), "Your regex should match <code>"favorite"</code>");' | |||
|  |   - text: 你的正则表达式应该匹配<code>"favourite"</code> | |||
|  |     testString: 'assert(favRegex.test("favourite"), "Your regex should match <code>"favourite"</code>");' | |||
|  |   - text: 你的正则表达式不应该匹配<code>"fav"</code> | |||
|  |     testString: 'assert(!favRegex.test("fav"), "Your regex should not match <code>"fav"</code>");' | |||
|  | 
 | |||
|  | ``` | |||
|  | 
 | |||
|  | </section> | |||
|  | 
 | |||
|  | ## Challenge Seed
 | |||
|  | <section id='challengeSeed'> | |||
|  | 
 | |||
|  | <div id='js-seed'> | |||
|  | 
 | |||
|  | ```js | |||
|  | let favWord = "favorite"; | |||
|  | let favRegex = /change/; // Change this line | |||
|  | let result = favRegex.test(favWord); | |||
|  | 
 | |||
|  | ``` | |||
|  | 
 | |||
|  | </div> | |||
|  | 
 | |||
|  | 
 | |||
|  | 
 | |||
|  | </section> | |||
|  | 
 | |||
|  | ## Solution
 | |||
|  | <section id='solution'> | |||
|  | 
 | |||
|  | ```js | |||
|  | // solution required | |||
|  | ``` | |||
|  | </section> |