2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244a8
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title: Storing Values with the Assignment Operator
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challengeType: 1
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videoUrl: ''
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localeTitle: 使用赋值运算符存储值
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---
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## Description
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<section id="description">在JavaScript中,您可以使用<dfn>赋值</dfn>运算符将值存储在变量中。 <code>myVariable = 5;</code>这将<code>Number</code>值<code>5</code>分配给<code>myVariable</code> 。作业总是从右到左。在将值分配给运算符左侧的变量之前,将解析<code>=</code>运算符右侧的所有内容。 <blockquote> myVar = 5; <br> myNum = myVar; </blockquote>这将为<code>myVar</code>分配<code>5</code> ,然后再次将<code>myVar</code>解析为<code>5</code>并将其分配给<code>myNum</code> 。 </section>
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## Instructions
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<section id="instructions">将值<code>7</code>分配给变量<code>a</code> 。分配的内容<code>a</code>变量<code>b</code> 。 </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: 不要更改行上方的代码
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2020-02-18 01:40:55 +09:00
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testString: assert(/var a;/.test(code) && /var b = 2;/.test(code));
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2018-10-10 18:03:03 -04:00
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- text: <code>a</code>的值应为7
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2020-02-18 01:40:55 +09:00
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testString: assert(typeof a === 'number' && a === 7);
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2018-10-10 18:03:03 -04:00
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- text: <code>b</code>的值应为7
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2020-02-18 01:40:55 +09:00
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testString: assert(typeof b === 'number' && b === 7);
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2018-10-10 18:03:03 -04:00
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- text: <code>a</code>应分配给<code>b</code> <code>=</code>
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2020-02-18 01:40:55 +09:00
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testString: assert(/b\s*=\s*a\s*;/g.test(code));
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2018-10-10 18:03:03 -04:00
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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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// Setup
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var a;
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var b = 2;
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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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if (typeof a != 'undefined') {
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a = undefined;
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}
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if (typeof b != 'undefined') {
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b = undefined;
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}
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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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