2018-10-10 22:03:03 +00:00
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---
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id: 56533eb9ac21ba0edf2244d3
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2021-03-13 17:31:57 +00:00
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title: 严格不等运算符
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2018-10-10 22:03:03 +00:00
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challengeType: 1
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2020-04-29 10:29:13 +00:00
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videoUrl: 'https://scrimba.com/c/cKekkUy'
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forumTopicId: 16791
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2021-01-13 02:31:00 +00:00
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dashedName: comparison-with-the-strict-inequality-operator
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2021-03-13 17:31:57 +00:00
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严格不相等运算符(`!==`)与全等运算符是相反的。 这意味着严格不相等并返回 `false` 的地方,用严格相等运算符会返回 `true`,*反之亦然*。 严格不相等运算符不会转换值的数据类型。
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2020-12-16 07:37:30 +00:00
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2021-03-13 17:31:57 +00:00
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**示例**
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2020-04-29 10:29:13 +00:00
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```js
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2021-03-13 17:31:57 +00:00
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3 !== 3
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3 !== '3'
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4 !== 3
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2020-04-29 10:29:13 +00:00
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```
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2021-03-13 17:31:57 +00:00
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按顺序,这些表达式会返回 `false`、`true`、`true`。
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2020-12-16 07:37:30 +00:00
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# --instructions--
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2018-10-10 22:03:03 +00:00
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2021-03-13 17:31:57 +00:00
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在 `if` 语句中,添加严格不相等运算符,这样函数在当 `val` 不严格等于 `17` 的时候,会返回 `Not Equal`。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2018-10-10 22:03:03 +00:00
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2021-03-13 17:31:57 +00:00
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`testStrictNotEqual(17)` 应该返回字符串 `Equal`
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert(testStrictNotEqual(17) === 'Equal');
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2018-10-10 22:03:03 +00:00
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```
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2021-03-13 17:31:57 +00:00
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`testStrictNotEqual("17")` 应该返回字符串 `Not Equal`
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2020-12-16 07:37:30 +00:00
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```js
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assert(testStrictNotEqual('17') === 'Not Equal');
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```
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2018-10-10 22:03:03 +00:00
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2021-03-13 17:31:57 +00:00
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`testStrictNotEqual(12)` 应该返回字符串 `Not Equal`
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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```js
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assert(testStrictNotEqual(12) === 'Not Equal');
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```
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2018-10-10 22:03:03 +00:00
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2021-03-13 17:31:57 +00:00
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`testStrictNotEqual("bob")` 应该返回字符串 `Not Equal`
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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```js
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assert(testStrictNotEqual('bob') === 'Not Equal');
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```
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2018-10-10 22:03:03 +00:00
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2021-03-13 17:31:57 +00:00
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应该使用 `!==` 运算符。
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2020-04-29 10:29:13 +00:00
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert(code.match(/(val\s*!==\s*\d+)|(\d+\s*!==\s*val)/g).length > 0);
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2018-10-10 22:03:03 +00:00
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```
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2020-04-29 10:29:13 +00:00
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2021-01-13 02:31:00 +00:00
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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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2020-12-16 07:37:30 +00:00
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# --solutions--
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2021-01-13 02:31:00 +00:00
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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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