2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244b8
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2020-12-16 00:37:30 -07:00
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title: 用 += 运算符连接字符串
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2018-10-10 18:03:03 -04:00
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challengeType: 1
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2020-04-29 18:29:13 +08:00
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videoUrl: 'https://scrimba.com/c/cbQmmC4'
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forumTopicId: 16803
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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我们还可以使用`+=`运算符来<dfn>concatenate</dfn>(拼接)字符串到现有字符串的结尾。对于那些被分割成几段的长的字符串来说,这一操作是非常有用的。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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**提示**
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注意空格。拼接操作不会在两个字符串之间添加空格,所以如果想要加上空格的话,你需要自己在字符串里面添加。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --instructions--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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通过使用`+=`操作符来连接这两个字符串:
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`"This is the first sentence. "`和`"This is the second sentence."`并赋给变量`myStr`。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`myStr`的值应该是`This is the first sentence. This is the second sentence.`。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(myStr === 'This is the first sentence. This is the second sentence.');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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使用`+=`操作符创建`myStr`变量。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(
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code.match(/\w\s*\+=\s*["']/g).length > 1 &&
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code.match(/\w\s*\=\s*["']/g).length > 1
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);
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2020-04-29 18:29:13 +08:00
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