2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244d3
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2020-12-16 00:37:30 -07:00
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title: 严格不等运算符
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2018-10-10 18:03:03 -04:00
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challengeType: 1
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2020-04-29 18:29:13 +08:00
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videoUrl: 'https://scrimba.com/c/cKekkUy'
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forumTopicId: 16791
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2021-01-13 03:31:00 +01:00
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dashedName: comparison-with-the-strict-inequality-operator
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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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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**示例**
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2020-04-29 18:29:13 +08:00
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```js
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3 !== 3 // false
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3 !== '3' // true
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4 !== 3 // true
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```
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2020-12-16 00:37:30 -07:00
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# --instructions--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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在`if`语句中,添加严格不相等运算符`!==`,这样如果`val`与`17`严格不相等的时候,函数会返回 "Not Equal"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`testStrictNotEqual(17)`应该返回 "Equal"。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(testStrictNotEqual(17) === 'Equal');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`testStrictNotEqual("17")`应该返回 "Not Equal"。
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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 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`testStrictNotEqual(12)`应该返回 "Not Equal"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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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 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`testStrictNotEqual("bob")`应该返回 "Not Equal"。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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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 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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应该使用 `!==` 运算符。
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2020-04-29 18:29:13 +08:00
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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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 18:03:03 -04:00
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```
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2020-04-29 18:29:13 +08:00
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2021-01-13 03:31:00 +01:00
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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 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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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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