102 lines
2.1 KiB
Markdown
102 lines
2.1 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244da
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cek4Efq'
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forumTopicId: 18207
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title: 介绍 else 语句
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---
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## Description
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<section id='description'>
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当<code>if</code>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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```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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</section>
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## Instructions
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<section id='instructions'>
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请把多个<code>if</code>语句合并为一个<code>if/else</code>语句。
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: 你应该只有一个<code>if</code>表达式。
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testString: assert(code.match(/if/g).length === 1);
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- text: 你应该使用一个<code>else</code>表达式。
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testString: assert(/else/g.test(code));
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- text: <code>testElse(4)</code>应该返回 "5 or Smaller"。
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testString: assert(testElse(4) === "5 or Smaller");
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- text: <code>testElse(5)</code>应该返回 "5 or Smaller"。
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testString: assert(testElse(5) === "5 or Smaller");
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- text: <code>testElse(6)</code>应该返回 "Bigger than 5"。
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testString: assert(testElse(6) === "Bigger than 5");
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- text: <code>testElse(10)</code>应该返回 "Bigger than 5"。
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testString: assert(testElse(10) === "Bigger than 5");
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- text: 不要修改上面和下面的代码。
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testString: assert(/var result = "";/.test(code) && /return result;/.test(code));
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function testElse(val) {
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var result = "";
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// Only change code below this line
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if (val > 5) {
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result = "Bigger than 5";
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}
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if (val <= 5) {
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result = "5 or Smaller";
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}
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// Only change code above this line
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return result;
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}
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// Change this value to test
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testElse(4);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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function testElse(val) {
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var result = "";
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if(val > 5) {
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result = "Bigger than 5";
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} else {
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result = "5 or Smaller";
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}
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return result;
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}
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```
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</section>
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