ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
83 lines
1.8 KiB
Markdown
83 lines
1.8 KiB
Markdown
---
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id: 599a789b454f2bbd91a3ff4d
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title: 比较不同值
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cm8PqCa'
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forumTopicId: 301174
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dashedName: practice-comparing-different-values
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---
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# --description--
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在上两个挑战中，我们学习了相等运算符 (`==`) 和严格相等运算符 (`===`)。现在让我们快速回顾并实践一下。
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如果要比较的值不是同一类型，相等运算符会先执行数据类型转换，然后比较值。而严格相等运算符只比较值，不会进行数据类型转换。
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由此可见，相等运算符和严格相等运算符的区别是：前者会执行隐式类型转换，后者不会。
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**示例**
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```js
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3 == '3' // returns true because JavaScript performs type conversion from string to number
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3 === '3' // returns false because the types are different and type conversion is not performed
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```
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**提示**
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在JavaScript中，你可以使用`typeof`运算符确定变量的类型或值，如下所示：
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```js
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typeof 3 // returns 'number'
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typeof '3' // returns 'string'
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```
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# --instructions--
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编辑器中的`compareEquality`函数使用相等运算符比较两个值。修改函数，使其仅在值严格相等时返回 "Equal" 。
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# --hints--
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`compareEquality(10, "10")`应该返回 "Not Equal"。
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```js
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assert(compareEquality(10, '10') === 'Not Equal');
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```
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`compareEquality("20", 20)`应该返回 "Not Equal"。
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```js
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assert(compareEquality('20', 20) === 'Not Equal');
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```
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你应该使用`===`运算符。
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```js
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assert(code.match(/===/g));
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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 compareEquality(a, b) {
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if (a == b) { // Change this line
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return "Equal";
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}
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return "Not Equal";
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}
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compareEquality(10, "10");
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```
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# --solutions--
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```js
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function compareEquality(a,b) {
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if (a === b) {
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return "Equal";
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}
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return "Not Equal";
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}
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```
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