97 lines
2.5 KiB
Markdown
97 lines
2.5 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392cf
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title: Write Reusable JavaScript with Functions
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challengeType: 1
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videoUrl: ''
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localeTitle: 用函数编写可重用的JavaScript
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---
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## Description
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<section id="description">在JavaScript中，我们可以将代码划分为称为<dfn>函数的</dfn>可重用部分。这是一个函数的例子： <blockquote> function functionName（）{ <br> console.log（“Hello World”）; <br> } </blockquote>您可以使用其名称后跟括号来调用或<dfn>调用</dfn>此函数，如下所示： <code>functionName();</code>每次调用该函数时，它都会在开发控制台上打印出<code>"Hello World"</code>消息。每次调用函数时，都会执行大括号之间的所有代码。 </section>
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## Instructions
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<section id="instructions"><ol><li>创建一个名为<code>reusableFunction</code>的函数，它将<code>"Hi World"</code>打印到开发控制台。 </li><li>调用该功能。 </li></ol></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>reusableFunction</code>应该是一个函数
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testString: 'assert(typeof reusableFunction === "function", "<code>reusableFunction</code> should be a function");'
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- text: <code>reusableFunction</code>应该将“Hi World”输出到开发控制台
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testString: 'assert("Hi World" === logOutput, "<code>reusableFunction</code> should output "Hi World" to the dev console");'
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- text: 定义后调用<code>reusableFunction</code>
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testString: 'assert(/^\s*reusableFunction\(\)\s*;/m.test(code), "Call <code>reusableFunction</code> after you define it");'
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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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// Example
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function ourReusableFunction() {
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console.log("Heyya, World");
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}
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ourReusableFunction();
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// Only change code below this line
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```
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</div>
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### Before Test
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<div id='js-setup'>
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```js
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var logOutput = "";
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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if(message && message.trim) logOutput = message.trim();
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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capture();
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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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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