72 lines
2.1 KiB
Markdown
72 lines
2.1 KiB
Markdown
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---
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id: bd7123c9c448eddfaeb5bdef
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title: Find the Length of a String
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challengeType: 1
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videoUrl: ''
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localeTitle: 找到字符串的长度
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---
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## Description
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<section id="description">您可以通过在字符串变量或字符串文字后面写<code>.length</code>来查找<code>String</code>值的长度。 <code>"Alan Peter".length; // 10</code>例如，如果我们创建了一个变量<code>var firstName = "Charles"</code> ，我们可以通过使用<code>firstName.length</code>属性找出字符串<code>"Charles"</code>长度。 </section>
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## Instructions
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<section id="instructions">使用<code>.length</code>属性计算<code>lastName</code>变量中的字符数，并将其分配给<code>lastNameLength</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: <code>lastNameLength</code>应该等于8。
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testString: 'assert((function(){if(typeof lastNameLength !== "undefined" && typeof lastNameLength === "number" && lastNameLength === 8){return true;}else{return false;}})(), "<code>lastNameLength</code> should be equal to eight.");'
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- text: 您应该使用<code>.length</code>来获取<code>lastName</code>的长度，如下所示： <code>lastName.length</code> 。
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testString: 'assert((function(){if(code.match(/\.length/gi) && code.match(/\.length/gi).length >= 2 && code.match(/var lastNameLength \= 0;/gi) && code.match(/var lastNameLength \= 0;/gi).length >= 1){return true;}else{return false;}})(), "You should be getting the length of <code>lastName</code> by using <code>.length</code> like this: <code>lastName.length</code>.");'
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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 firstNameLength = 0;
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var firstName = "Ada";
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firstNameLength = firstName.length;
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// Setup
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var lastNameLength = 0;
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var lastName = "Lovelace";
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// Only change code below this line.
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lastNameLength = lastName;
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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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