115 lines
1.8 KiB
Markdown
115 lines
1.8 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244db
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title: 介紹 else if 語句
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/caeJ2hm'
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forumTopicId: 18206
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dashedName: introducing-else-if-statements
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---
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# --description--
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如果你有多個條件語句，你可以通過 `else if` 語句把 `if` 語句鏈起來。
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```js
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if (num > 15) {
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return "Bigger than 15";
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} else if (num < 5) {
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return "Smaller than 5";
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} else {
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return "Between 5 and 15";
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}
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```
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# --instructions--
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使用 `else if` 實現同樣的效果。
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# --hints--
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你應該至少有兩個 `else` 表達式。
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```js
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assert(code.match(/else/g).length > 1);
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```
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你應該至少有兩個 `if` 表達式。
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```js
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assert(code.match(/if/g).length > 1);
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```
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應該關閉每一個 `if else` 代碼塊。
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```js
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assert(
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code.match(
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/if\s*\((.+)\)\s*\{[\s\S]+\}\s*else\s+if\s*\((.+)\)\s*\{[\s\S]+\}\s*else\s*\{[\s\S]+\s*\}/
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)
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);
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```
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`testElseIf(0)` 應該返回字符串 `Smaller than 5`
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```js
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assert(testElseIf(0) === 'Smaller than 5');
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```
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`testElseIf(5)` 應該返回字符串 `Between 5 and 10`
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```js
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assert(testElseIf(5) === 'Between 5 and 10');
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```
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`testElseIf(7)` 應該返回字符串 `Between 5 and 10`
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```js
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assert(testElseIf(7) === 'Between 5 and 10');
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```
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`testElseIf(10)` 應該返回字符串 `Between 5 and 10`
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```js
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assert(testElseIf(10) === 'Between 5 and 10');
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```
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`testElseIf(12)` 應該返回字符串 `Greater than 10`
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```js
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assert(testElseIf(12) === 'Greater than 10');
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```
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# --seed--
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## --seed-contents--
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```js
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function testElseIf(val) {
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if (val > 10) {
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return "Greater than 10";
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}
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if (val < 5) {
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return "Smaller than 5";
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}
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return "Between 5 and 10";
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}
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testElseIf(7);
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```
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# --solutions--
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```js
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function testElseIf(val) {
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if(val > 10) {
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return "Greater than 10";
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} else if(val < 5) {
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return "Smaller than 5";
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} else {
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return "Between 5 and 10";
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}
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}
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```
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