60 lines
2.0 KiB
Markdown
60 lines
2.0 KiB
Markdown
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---
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id: 587d7b7e367417b2b2512b24
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title: Use the Conditional (Ternary) Operator
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challengeType: 1
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videoUrl: ''
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localeTitle: 使用条件（三元）运算符
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---
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## Description
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<section id="description"> <dfn>条件运算符</dfn> （也称为<dfn>三元运算符</dfn> ）可以用作一行if-else表达式。语法是： <code>condition ? statement-if-true : statement-if-false;</code>以下函数使用if-else语句来检查条件： <blockquote> function findGreater（a，b）{ <br> if（a> b）{ <br>返回“a更大”; <br> } <br>其他{ <br>返回“b更大”; <br> } <br> } </blockquote>这可以使用<code>conditional operator</code>重写： <blockquote> function findGreater（a，b）{ <br>返回a> b？ “a更大”：“b更大”; <br> } </blockquote></section>
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## Instructions
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<section id="instructions">在<code>checkEqual</code>函数中使用<code>conditional operator</code>来检查两个数字是否相等。该函数应返回true或false。 </section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>checkEqual</code>应该使用<code>conditional operator</code>
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testString: 'assert(/.+?\s*?\?\s*?.+?\s*?:\s*?.+?/gi.test(code), "<code>checkEqual</code> should use the <code>conditional operator</code>");'
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- text: '<code>checkEqual(1, 2)</code>应该返回false'
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testString: 'assert(checkEqual(1, 2) === false, "<code>checkEqual(1, 2)</code> should return false");'
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- text: '<code>checkEqual(1, 1)</code>应该返回true'
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testString: 'assert(checkEqual(1, 1) === true, "<code>checkEqual(1, 1)</code> should return true");'
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- text: '<code>checkEqual(1, -1)</code>应该返回false'
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testString: 'assert(checkEqual(1, -1) === false, "<code>checkEqual(1, -1)</code> should return false");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function checkEqual(a, b) {
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}
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checkEqual(1, 2);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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