84 lines
1.7 KiB
Markdown
84 lines
1.7 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244b7
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title: 用加號運算符連接字符串
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cNpM8AN'
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forumTopicId: 16802
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dashedName: concatenating-strings-with-plus-operator
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---
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# --description--
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在 JavaScript 中，當 `+` 操作符被用於一個 `String` 類型的值的時候，它被稱作<dfn>拼接</dfn>操作符。 你可以通過<dfn>拼接</dfn>其他字符串來創建一個新的字符串。
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**例如：**
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```js
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'My name is Alan,' + ' I concatenate.'
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```
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**提示：**注意空格。 拼接操作不會在兩個字符串之間添加空格。所以，如果想加上空格的話，你需要自己在字符串裏面添加。
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例如：
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```js
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var ourStr = "I come first. " + "I come second.";
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```
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字符串 `I come first. I come second.` 將顯示在控制檯中。
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# --instructions--
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使用 `+` 操作符連接字符串`This is the start.` 和 `This is the end.` 賦值給 `myStr` 。
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# --hints--
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`myStr` 的值應該是 `This is the start. This is the end.`
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```js
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assert(myStr === 'This is the start. This is the end.');
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```
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應使用 `+` 操作符創建 `myStr`。
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```js
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assert(code.match(/(["']).*\1\s*\+\s*(["']).*\2/g));
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```
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應使用 `var` 關鍵字創建 `myStr`。
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```js
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assert(/var\s+myStr/.test(code));
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```
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應把結果賦值給 `myStr` 變量。
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```js
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assert(/myStr\s*=/.test(code));
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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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return 'myStr = "' + myStr + '"';
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} else {
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return 'myStr is not a string';
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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 = "This is the start. " + "This is the end.";
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```
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