29 lines
851 B
Markdown
29 lines
851 B
Markdown
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---
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title: Add Elements to the End of an Array Using concat Instead of push
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localeTitle: 使用concat将元素添加到数组的末尾而不是push
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---
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## 使用concat将元素添加到数组的末尾而不是push
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在`push`方法将新元素添加到原始数组的末尾的地方， `concat`方法创建一个新数组，其中包含原始数组和新元素中的元素。使用`concat`时，原始数组保持不变。
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#### 相关链接：
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* [Array.prototype.concat（）](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/concat)
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## 解
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```javascript
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function nonMutatingPush(original, newItem) {
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// Add your code below this line
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return original.concat(newItem);
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// Add your code above this line
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}
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var first = [1, 2, 3];
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var second = [4, 5];
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nonMutatingPush(first, second);
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```
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