freeCodeCamp/guide/chinese/certifications/javascript-algorithms-and-data-structures/basic-data-structures/copy-an-array-with-the-spread-operator/index.md

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Copy an Array with the Spread Operator	使用Spread Operator复制数组

使用Spread Operator复制数组

• 示例中的最后一个提示告诉您使用最近学习的方法。
• spread运算符将所有元素复制到一个新的空对象中。

```的JavaScript while（num> = 1）{ newArr = [... arr] num--; }

- The code above will copy all of the elements into `newArr` but will also reinitialise `newArr` with every new iteration of the while loop. 
 - A new variable should first be initialised using the spread operator - `let obj = [...arr];` - then this variable should be added to the `newArr` for every iteration of the while loop. 
 
 ## Solution: 

JavaScript的 function copyMachine（arr，num）{ 让newArr = []; while（num> = 1）{ //更改此行下方的代码 newArr.push（[... ARR]）; //更改此行以上的代码 num--; } 返回newArr; }

//在此处更改代码以测试不同的情况： console.log（copyMachine（[true，false，true]，2））; ```