2018-10-10 18:03:03 -04:00
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---
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id: bd7123c9c444eddfaeb5bdef
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2020-12-16 00:37:30 -07:00
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title: 声明字符串变量
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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/c2QvWU6'
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forumTopicId: 17557
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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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之前我们写过这样的代码:
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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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`var myName = "your name";`
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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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`"your name"`被称作<dfn>字符串变量</dfn>。字符串是用单引号或双引号包裹起来的一连串的零个或多个字符。
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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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创建两个新的`字符串变量`:`myFirstName`和`myLastName`,并用你的姓和名分别为它们赋值。
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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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`myFirstName`应该是一个字符串,并且至少包含一个字符。
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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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(function () {
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if (
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typeof myFirstName !== 'undefined' &&
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typeof myFirstName === 'string' &&
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myFirstName.length > 0
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) {
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return true;
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} else {
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return false;
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}
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})()
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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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`myLastName`应该是一个字符串,并且至少包含一个字符。
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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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(function () {
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if (
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typeof myLastName !== 'undefined' &&
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typeof myLastName === 'string' &&
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myLastName.length > 0
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) {
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return true;
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} else {
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return false;
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}
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})()
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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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