67 lines
1.5 KiB
Markdown
67 lines
1.5 KiB
Markdown
---
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id: 587d7db7367417b2b2512b9e
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title: 匹配字符串的末尾
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challengeType: 1
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forumTopicId: 301352
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dashedName: match-ending-string-patterns
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---
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# --description--
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在上一个挑战中，学习了使用脱字符号来搜寻字符串的开始位置。 还有一种方法可以搜寻字符串末尾的匹配模式。
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可以使用正则表达式的美元符号 `$` 来搜寻字符串的结尾。
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```js
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let theEnding = "This is a never ending story";
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let storyRegex = /story$/;
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storyRegex.test(theEnding);
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let noEnding = "Sometimes a story will have to end";
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storyRegex.test(noEnding);
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```
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第一次 `test` 调用将返回 `true`, 而第二次调用将返回 `false`。
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# --instructions--
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使用锚点字符 `$` 来匹配字符串 `caboose` 在字符串末尾 `caboose`。
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# --hints--
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你应该在正则表达式使用美元符号 `$` 来搜寻 `caboose`。
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```js
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assert(lastRegex.source == 'caboose$');
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```
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你的正则表达式不应该使用任何标志。
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```js
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assert(lastRegex.flags == '');
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```
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你应该在字符串 `The last car on a train is the caboose` 的末尾匹配 `caboose`。
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```js
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lastRegex.lastIndex = 0;
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assert(lastRegex.test('The last car on a train is the caboose'));
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```
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# --seed--
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## --seed-contents--
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```js
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let caboose = "The last car on a train is the caboose";
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let lastRegex = /change/; // Change this line
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let result = lastRegex.test(caboose);
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```
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# --solutions--
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```js
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let caboose = "The last car on a train is the caboose";
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let lastRegex = /caboose$/; // Change this line
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let result = lastRegex.test(caboose);
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```
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