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

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---
id: 56bbb991ad1ed5201cd392cb
title: 使用 push() 操作数组
challengeType: 1
videoUrl: 'https://scrimba.com/c/cnqmVtJ'
forumTopicId: 18237
dashedName: manipulate-arrays-with-push
---
# --description--
一个将数据添加到数组末尾的简单方法是 `push()` 函数。
`.push()` 接受一个或多个参数(<dfn>parameters</dfn>),并把它压入到数组的末尾。
示例:
```js
var arr1 = [1,2,3];
arr1.push(4);
var arr2 = ["Stimpson", "J", "cat"];
arr2.push(["happy", "joy"]);
```
`arr1` 现在值为 `[1, 2, 3, 4]``arr2` 值为 `["Stimpson", "J", "cat", ["happy", "joy"]]`
# --instructions--
把`["dog", 3]` 压入到 `myArray` 变量的末尾。
# --hints--
`myArray` 现在应该等于 `[["John", 23], ["cat", 2], ["dog", 3]]`
```js
assert(
(function (d) {
if (
d[2] != undefined &&
d[0][0] == 'John' &&
d[0][1] === 23 &&
d[2][0] == 'dog' &&
d[2][1] === 3 &&
d[2].length == 2
) {
return true;
} else {
return false;
}
})(myArray)
);
```
# --seed--
## --after-user-code--
```js
(function(z){return 'myArray = ' + JSON.stringify(z);})(myArray);
```
## --seed-contents--
```js
// Setup
var myArray = [["John", 23], ["cat", 2]];
// Only change code below this line
```
# --solutions--
```js
var myArray = [["John", 23], ["cat", 2]];
myArray.push(["dog",3]);
```