2021-05-05 10:13:49 -07:00
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---
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id: 56533eb9ac21ba0edf2244d2
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title: 不等運算符
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cdBm9Sr'
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forumTopicId: 16787
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dashedName: comparison-with-the-inequality-operator
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---
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# --description--
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2021-06-14 23:47:03 +09:00
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不相等運算符(`!=`)與相等運算符是相反的。 這意味着不相等並返回 `false` 的地方,用相等運算符會返回 `true`,*反之亦然*。 與相等運算符類似,不相等運算符在比較的時候也會轉換值的數據類型。
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2021-05-05 10:13:49 -07:00
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**例如**
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```js
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2022-03-23 19:52:04 +05:30
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1 != 2 // true
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1 != "1" // false
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1 != '1' // false
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1 != true // false
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0 != false // false
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2021-05-05 10:13:49 -07:00
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```
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# --instructions--
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2022-03-23 19:52:04 +05:30
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在 `if` 語句中添加不等式運算符 `!=` 以便函數在 `val` 不等於 `99` 時返回字符串 `Not Equal`。
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2021-05-05 10:13:49 -07:00
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# --hints--
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`testNotEqual(99)` 應該返回字符串 `Equal`
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```js
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assert(testNotEqual(99) === 'Equal');
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```
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`testNotEqual("99")` 應該返回字符串 `Equal`
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```js
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assert(testNotEqual('99') === 'Equal');
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```
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`testNotEqual(12)` 應該返回字符串 `Not Equal`
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```js
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assert(testNotEqual(12) === 'Not Equal');
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```
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`testNotEqual("12")` 應該返回字符串 `Not Equal`
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```js
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assert(testNotEqual('12') === 'Not Equal');
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```
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`testNotEqual("bob")` 應該返回字符串 `Not Equal`
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```js
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assert(testNotEqual('bob') === 'Not Equal');
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```
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2022-03-23 19:52:04 +05:30
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你應該使用 `!=` 運算符
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2021-05-05 10:13:49 -07:00
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```js
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assert(code.match(/(?!!==)!=/));
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```
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# --seed--
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## --seed-contents--
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```js
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// Setup
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function testNotEqual(val) {
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if (val) { // Change this line
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return "Not Equal";
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}
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return "Equal";
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}
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testNotEqual(10);
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```
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# --solutions--
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```js
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function testNotEqual(val) {
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if (val != 99) {
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return "Not Equal";
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}
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return "Equal";
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}
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```
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