86 lines
1.6 KiB
Markdown
86 lines
1.6 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244d3
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title: 嚴格不等運算符
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cKekkUy'
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forumTopicId: 16791
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dashedName: comparison-with-the-strict-inequality-operator
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---
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# --description--
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嚴格不相等運算符（`!==`）與全等運算符是相反的。 這意味着嚴格不相等並返回 `false` 的地方，用嚴格相等運算符會返回 `true`，*反之亦然*。 嚴格不相等運算符不會轉換值的數據類型。
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**示例**
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```js
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3 !== 3
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3 !== '3'
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4 !== 3
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```
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按順序，這些表達式會返回 `false`、`true`、`true`。
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# --instructions--
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在 `if` 語句中，添加嚴格不相等運算符，這樣函數在當 `val` 不嚴格等於 `17` 的時候，會返回 `Not Equal`。
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# --hints--
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`testStrictNotEqual(17)` 應該返回字符串 `Equal`
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```js
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assert(testStrictNotEqual(17) === 'Equal');
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```
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`testStrictNotEqual("17")` 應該返回字符串 `Not Equal`
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```js
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assert(testStrictNotEqual('17') === 'Not Equal');
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```
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`testStrictNotEqual(12)` 應該返回字符串 `Not Equal`
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```js
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assert(testStrictNotEqual(12) === 'Not Equal');
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```
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`testStrictNotEqual("bob")` 應該返回字符串 `Not Equal`
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```js
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assert(testStrictNotEqual('bob') === 'Not Equal');
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```
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應該使用 `!==` 運算符。
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```js
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assert(code.match(/(val\s*!==\s*\d+)|(\d+\s*!==\s*val)/g).length > 0);
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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 testStrictNotEqual(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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testStrictNotEqual(10);
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```
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# --solutions--
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```js
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function testStrictNotEqual(val) {
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if (val !== 17) {
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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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