2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244d2
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2021-03-14 21:20:39 -06:00
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title: 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/cdBm9Sr'
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forumTopicId: 16787
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2021-01-13 03:31:00 +01:00
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dashedName: comparison-with-the-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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2021-06-14 23:47:03 +09:00
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不相等运算符(`!=`)与相等运算符是相反的。 这意味着不相等并返回 `false` 的地方,用相等运算符会返回 `true`,*反之亦然*。 与相等运算符类似,不相等运算符在比较的时候也会转换值的数据类型。
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2020-12-16 00:37:30 -07:00
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2021-03-14 21:20:39 -06:00
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**例如**
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2020-04-29 18:29:13 +08:00
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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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2020-04-29 18:29:13 +08:00
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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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2022-03-23 19:52:04 +05:30
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在 `if` 语句中添加不等式运算符 `!=` 以便函数在 `val` 不等于 `99` 时返回字符串 `Not Equal`。
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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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2021-03-14 21:20:39 -06:00
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`testNotEqual(99)` 应该返回字符串 `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(testNotEqual(99) === 'Equal');
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```
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2018-10-10 18:03:03 -04:00
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2021-03-14 21:20:39 -06:00
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`testNotEqual("99")` 应该返回字符串 `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(testNotEqual('99') === 'Equal');
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2018-10-10 18:03:03 -04:00
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```
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2021-03-14 21:20:39 -06:00
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`testNotEqual(12)` 应该返回字符串 `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(testNotEqual(12) === 'Not Equal');
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```
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2018-10-10 18:03:03 -04:00
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2021-03-14 21:20:39 -06:00
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`testNotEqual("12")` 应该返回字符串 `Not Equal`
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2020-12-16 00:37:30 -07:00
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```js
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assert(testNotEqual('12') === 'Not Equal');
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```
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2018-10-10 18:03:03 -04:00
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2021-03-14 21:20:39 -06:00
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`testNotEqual("bob")` 应该返回字符串 `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(testNotEqual('bob') === 'Not Equal');
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```
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2018-10-10 18:03:03 -04:00
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2022-03-23 19:52:04 +05:30
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你应该使用 `!=` 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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assert(code.match(/(?!!==)!=/));
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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 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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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 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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