freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-an.../basic-javascript/manipulate-arrays-with-shif...

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---
id: 56bbb991ad1ed5201cd392cd
title: Manipulate Arrays With shift()
challengeType: 1
videoUrl: ''
localeTitle: 使用shift操纵数组
---
## Description
<section id="description"> <code>pop()</code>总是删除数组的最后一个元素。如果你想删除第一个怎么办?这就是<code>.shift()</code>用武之地。它就像<code>.pop()</code>一样工作,除了它删除了第一个元素而不是最后一个元素。 </section>
## Instructions
<section id="instructions">使用<code>.shift()</code>函数从<code>myArray</code>删除第一项将“shift off”值分配给<code>removedFromMyArray</code></section>
## Tests
<section id='tests'>
```yml
tests:
- text: '<code>myArray</code>现在应该等于<code>[[&quot;dog&quot;, 3]]</code> 。'
testString: 'assert((function(d){if(d[0][0] == "dog" && d[0][1] === 3 && d[1] == undefined){return true;}else{return false;}})(myArray), "<code>myArray</code> should now equal <code>[["dog", 3]]</code>.");'
- text: '<code>removedFromMyArray</code>应该包含<code>[&quot;John&quot;, 23]</code> 。'
testString: 'assert((function(d){if(d[0] == "John" && d[1] === 23 && typeof removedFromMyArray === "object"){return true;}else{return false;}})(removedFromMyArray), "<code>removedFromMyArray</code> should contain <code>["John", 23]</code>.");'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Example
var ourArray = ["Stimpson", "J", ["cat"]];
var removedFromOurArray = ourArray.shift();
// removedFromOurArray now equals "Stimpson" and ourArray now equals ["J", ["cat"]].
// Setup
var myArray = [["John", 23], ["dog", 3]];
// Only change code below this line.
var removedFromMyArray;
```
</div>
### After Test
<div id='js-teardown'>
```js
console.info('after the test');
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>