2018-10-10 18:03:03 -04:00
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---
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id: 56533eb9ac21ba0edf2244ed
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challengeType: 1
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2020-04-29 18:29:13 +08:00
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videoUrl: 'https://scrimba.com/c/cbQmZfa'
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forumTopicId: 16656
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2020-10-01 17:54:21 +02:00
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title: 将变量附加到字符串
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2018-10-10 18:03:03 -04:00
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---
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## Description
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2020-04-29 18:29:13 +08:00
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<section id='description'>
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我们不仅可以创建出多行的字符串,还可以使用加等号(<code>+=</code>)运算符来将变量追加到字符串。
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</section>
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2018-10-10 18:03:03 -04:00
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## Instructions
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2020-04-29 18:29:13 +08:00
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<section id='instructions'>
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设置变量<code>someAdjective</code>的值,并使用<code>+=</code>运算符把它追加到变量<code>myStr</code>上。
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</section>
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2018-10-10 18:03:03 -04:00
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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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2020-04-29 18:29:13 +08:00
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- text: <code>someAdjective</code>应该是一个至少包含三个字符的字符串。
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2020-02-18 01:40:55 +09:00
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testString: assert(typeof someAdjective !== 'undefined' && someAdjective.length > 2);
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2020-04-29 18:29:13 +08:00
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- text: 使用<code>+=</code>操作符把<code>someAdjective</code>追加到<code>myStr</code>的后面。
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2020-02-18 01:40:55 +09:00
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testString: assert(code.match(/myStr\s*\+=\s*someAdjective\s*/).length > 0);
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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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// Example
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var anAdjective = "awesome!";
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var ourStr = "freeCodeCamp is ";
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ourStr += anAdjective;
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// Only change code below this line
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var someAdjective;
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var myStr = "Learning to code is ";
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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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2020-04-29 18:29:13 +08:00
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(function(){
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var output = [];
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if(typeof someAdjective === 'string') {
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output.push('someAdjective = "' + someAdjective + '"');
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} else {
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output.push('someAdjective is not a string');
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}
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if(typeof myStr === 'string') {
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output.push('myStr = "' + myStr + '"');
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} else {
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output.push('myStr is not a string');
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}
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return output.join('\n');
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})();
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2018-10-10 18:03:03 -04:00
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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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2020-04-29 18:29:13 +08:00
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2018-10-10 18:03:03 -04:00
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```js
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2020-04-29 18:29:13 +08:00
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var anAdjective = "awesome!";
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var ourStr = "freeCodeCamp is ";
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ourStr += anAdjective;
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var someAdjective = "neat";
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var myStr = "Learning to code is ";
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myStr += someAdjective;
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2018-10-10 18:03:03 -04:00
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```
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2020-04-29 18:29:13 +08:00
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2018-10-10 18:03:03 -04:00
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</section>
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