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87 lines
2.5 KiB
Markdown
87 lines
2.5 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244b6
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title: 转义字符
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cvmqRh6'
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forumTopicId: 17567
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dashedName: escape-sequences-in-strings
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---
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# --description--
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引号不是字符串中唯一可以被转义（<dfn>escaped</dfn>）的字符。 Escape sequences allow you to use characters you may not otherwise be able to use in a string.
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<table class='table table-striped'><thead><tr><th>代码</th><th>输出</th></tr></thead><tbody><tr><td><code>\'</code></td><td>单引号</td></tr><tr><td><code>\"</code></td><td>双引号</td></tr><tr><td><code>\\</code></td><td>反斜杠</td></tr><tr><td><code>\n</code></td><td>换行符</td></tr><tr><td><code>\t</code></td><td>制表符</td></tr><tr><td><code>\r</code></td><td>回车</td></tr><tr><td><code>\b</code></td><td>退格</td></tr><tr><td><code>\f</code></td><td>换页符</td></tr></tbody></table>
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*Note that the backslash itself must be escaped in order to display as a backslash.*
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# --instructions--
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Assign the following three lines of text into the single variable `myStr` using escape sequences.
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<blockquote>FirstLine<br> \SecondLine<br>ThirdLine</blockquote>
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You will need to use escape sequences to insert special characters correctly. You will also need to follow the spacing as it looks above, with no spaces between escape sequences or words.
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**Note:** The indentation for `SecondLine` is achieved with the tab escape character, not spaces.
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# --hints--
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`myStr` should not contain any spaces
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```js
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assert(!/ /.test(myStr));
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```
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`myStr` should contain the strings `FirstLine`, `SecondLine` and `ThirdLine` (remember case sensitivity)
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```js
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assert(
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/FirstLine/.test(myStr) && /SecondLine/.test(myStr) && /ThirdLine/.test(myStr)
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);
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```
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`FirstLine` should be followed by the newline character `\n`
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```js
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assert(/FirstLine\n/.test(myStr));
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```
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`myStr` should contain a tab character `\t` which follows a newline character
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```js
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assert(/\n\t/.test(myStr));
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```
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`SecondLine` should be preceded by the backslash character `\`
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```js
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assert(/\\SecondLine/.test(myStr));
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```
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There should be a newline character between `SecondLine` and `ThirdLine`
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```js
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assert(/SecondLine\nThirdLine/.test(myStr));
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```
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`myStr` should only contain characters shown in the instructions
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```js
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assert(myStr === 'FirstLine\n\t\\SecondLine\nThirdLine');
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```
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# --seed--
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## --seed-contents--
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```js
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const myStr = ""; // Change this line
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```
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# --solutions--
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```js
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const myStr = "FirstLine\n\t\\SecondLine\nThirdLine";
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```
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