59 lines
1.6 KiB
Markdown
59 lines
1.6 KiB
Markdown
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---
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id: 5cdafbb0291309899753167f
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challengeType: 1
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forumTopicId: 301197
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localeTitle: 创建一个 JavaScript Promise
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---
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## Description
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<section id='description'>
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Promise 是异步编程的一种解决方案 - 它在未来的某时会生成一个值。任务完成，分执行成功和执行失败两种情况。<code>Promise</code> 是构造器函数，需要通过 <code>new</code> 关键字来创建。构造器参数是一个函数，该函数有两个参数 - <code>resolve</code> 和 <code>reject</code>。通过它们来判断 promise 的执行结果。用法如下：
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```js
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const myPromise = new Promise((resolve, reject) => {
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});
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```
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</section>
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## Instructions
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<section id='instructions'>
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创建一个名为 <code>makeServerRequest</code> 的 promise。给构造器函数传入 <code>resolve</code> 和 <code>reject</code> 两个参数。
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</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: 应该给名为 <code>makeServerRequest</code> 的变量指定一个 promise。
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testString: assert(makeServerRequest instanceof Promise);
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- text: promise 应该接收一个函数做为参数，该函数应该包含 <code>resolve</code> 和 <code>reject</code> 两个参数。
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testString: assert(code.match(/Promise\(\s*(function\s*\(\s*resolve\s*,\s*reject\s*\)\s*{|\(\s*resolve\s*,\s*reject\s*\)\s*=>\s*{)[^}]*}/g));
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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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```
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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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const makeServerRequest = new Promise((resolve, reject) => {
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});
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```
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</section>
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