73 lines
1.7 KiB
Markdown
73 lines
1.7 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244b5
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title: 轉義字符串中的引號
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c2QvgSr'
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forumTopicId: 17568
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dashedName: escaping-literal-quotes-in-strings
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---
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# --description--
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定義一個字符串必須要用單引號或雙引號來包裹它。 那麼當你的字符串裏面包含引號 `"` 或者 `'` 時該怎麼辦呢?
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在 JavaScript 中，可以通過在引號前面使用<dfn>反斜槓</dfn>（`\`）來<dfn>轉義</dfn>引號。
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```js
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var sampleStr = "Alan said, \"Peter is learning JavaScript\".";
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```
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有了轉義符號，JavaScript 就知道這個單引號或雙引號並不是字符串的結尾，而是字符串內的字符。 所以，上面的字符串打印到控制檯的結果爲：
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```js
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Alan said, "Peter is learning JavaScript".
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```
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# --instructions--
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使用<dfn>反斜槓</dfn>給 `myStr` 變量賦值一個字符串，這樣如果你要打印它到控制檯，將會看到：
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```js
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I am a "double quoted" string inside "double quotes".
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```
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# --hints--
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你的代碼中應該包含兩個雙引號（`"`）以及四個轉義的雙引號（`\"`）。
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```js
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assert(code.match(/\\"/g).length === 4 && code.match(/[^\\]"/g).length === 2);
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```
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變量 myStr 應該包含字符串 `I am a "double quoted" string inside "double quotes".`
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```js
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assert(/I am a "double quoted" string inside "double quotes(\."|"\.)$/.test(myStr));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(){
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if(typeof myStr === 'string') {
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console.log("myStr = \"" + myStr + "\"");
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} else {
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console.log("myStr is undefined");
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}
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})();
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```
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## --seed-contents--
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```js
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var myStr = ""; // Change this line
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```
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# --solutions--
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```js
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var myStr = "I am a \"double quoted\" string inside \"double quotes\".";
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```
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