ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
66 lines
1.3 KiB
Markdown
66 lines
1.3 KiB
Markdown
---
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id: bd7123c9c448eddfaeb5bdef
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title: 查找字符串的长度
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cvmqEAd'
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forumTopicId: 18182
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dashedName: find-the-length-of-a-string
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---
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# --description--
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你可以通过在字符串变量或字符串后面写上`.length`来获得字符串变量值的长度。
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`"Alan Peter".length; // 10`
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例如，我们创建了一个变量`var firstName = "Charles"`，我们就可以通过使用`firstName.length`来获得`"Charles"`字符串的长度。
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# --instructions--
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使用`.length`属性来获得变量`lastName`的长度，并把它赋值给变量`lastNameLength`。
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# --hints--
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不能改变 `// Setup` 部分声明的变量。
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```js
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assert(
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code.match(/var lastNameLength = 0;/) &&
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code.match(/var lastName = "Lovelace";/)
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);
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```
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`lastNameLength`应该等于 8。
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```js
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assert(typeof lastNameLength !== 'undefined' && lastNameLength === 8);
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```
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你应该使用 `.length` 获取 `lastName` 的长度，像这样 `lastName.length`。
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```js
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assert(code.match(/=\s*lastName\.length/g) && !code.match(/lastName\s*=\s*8/));
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```
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# --seed--
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## --seed-contents--
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```js
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// Setup
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var lastNameLength = 0;
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var lastName = "Lovelace";
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// Only change code below this line
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lastNameLength = lastName;
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```
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# --solutions--
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```js
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var lastNameLength = 0;
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var lastName = "Lovelace";
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lastNameLength = lastName.length;
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```
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