2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244da
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2020-12-16 00:37:30 -07:00
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title: 介绍 else 语句
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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/cek4Efq'
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forumTopicId: 18207
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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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当`if`语句的条件为真,大括号里的代码执行,那如果条件为假呢?正常情况下什么也不会发生。使用else语句,可以执行当条件为假时相应的代码。
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2020-04-29 18:29:13 +08:00
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```js
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if (num > 10) {
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return "Bigger than 10";
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} else {
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return "10 or Less";
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}
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```
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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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请把多个`if`语句合并为一个`if/else`语句。
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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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你应该只有一个`if`表达式。
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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(code.match(/if/g).length === 1);
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```
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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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你应该使用一个`else`表达式。
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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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```js
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assert(/else/g.test(code));
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```
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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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`testElse(4)`应该返回 "5 or Smaller"。
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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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```js
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assert(testElse(4) === '5 or Smaller');
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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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`testElse(5)`应该返回 "5 or Smaller"。
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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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```js
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assert(testElse(5) === '5 or Smaller');
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```
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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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`testElse(6)`应该返回 "Bigger than 5"。
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```js
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assert(testElse(6) === 'Bigger than 5');
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```
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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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`testElse(10)`应该返回 "Bigger than 5"。
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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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```js
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assert(testElse(10) === 'Bigger than 5');
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```
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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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不要修改上面和下面的代码。
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2020-04-29 18:29:13 +08:00
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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(/var result = "";/.test(code) && /return result;/.test(code));
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2018-10-10 18:03:03 -04:00
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```
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2020-04-29 18:29:13 +08:00
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2020-12-16 00:37:30 -07:00
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# --solutions--
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