2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244d2
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2020-12-16 00:37:30 -07:00
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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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不相等运算符(`!=`)与相等运算符是相反的。这意味着不相等运算符中,如果“不为真”并且返回`false`的地方,在相等运算符中会返回`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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**例如**
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2020-04-29 18:29:13 +08:00
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```js
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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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```
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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,添加不相等运算符`!=`,这样函数在当`val`不等于 `99`的时候,会返回 "Not Equal"。
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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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`testNotEqual(99)`应该返回 "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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2020-12-16 00:37:30 -07:00
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`testNotEqual("99")`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(testNotEqual('99') === '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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`testNotEqual(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(testNotEqual(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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`testNotEqual("12")`应该返回 "Not Equal"。
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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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2020-12-16 00:37:30 -07:00
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`testNotEqual("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(testNotEqual('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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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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2020-12-16 00:37:30 -07:00
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assert(code.match(/(?!!==)!=/));
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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 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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