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79 lines
1.4 KiB
Markdown
79 lines
1.4 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392cb
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title: 使用 push 方法操作数组
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cnqmVtJ'
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forumTopicId: 18237
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dashedName: manipulate-arrays-with-push
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---
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# --description--
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一个将数据添加到数组末尾的简单方式是使用 `push()` 方法。
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`push()` 方法需要一个或多个 <dfn>参数</dfn> 并将它们根据出现顺序追加到数组的末尾。 它返回数组的新长度。
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示例：
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```js
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const arr1 = [1, 2, 3];
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arr1.push(4, 5);
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const arr2 = ["Stimpson", "J", "cat"];
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arr2.push(["happy", "joy"]);
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```
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`arr1` 现在值为 `[1, 2, 3, 4, 5]`，`arr2` 的值为 `["Stimpson", "J", "cat", ["happy", "joy"]]`。
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# --instructions--
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把`["dog", 3]` 压入到 `myArray` 变量的末尾。
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# --hints--
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`myArray` 现在应该等于 `[["John", 23], ["cat", 2], ["dog", 3]]`。
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```js
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assert(
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(function (d) {
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if (
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d[2] != undefined &&
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d[0][0] == 'John' &&
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d[0][1] === 23 &&
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d[2][0] == 'dog' &&
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d[2][1] === 3 &&
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d[2].length == 2
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) {
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return true;
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} else {
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return false;
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}
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})(myArray)
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);
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```
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# --seed--
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## --after-user-code--
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```js
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(function(z){return 'myArray = ' + JSON.stringify(z);})(myArray);
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```
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## --seed-contents--
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```js
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// Setup
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const myArray = [["John", 23], ["cat", 2]];
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// Only change code below this line
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```
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# --solutions--
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```js
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const myArray = [["John", 23], ["cat", 2]];
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myArray.push(["dog",3]);
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```
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