## flatten + [link](./flatten "Link to this entry.") + [source](https://github.com/lodash/lodash/blob/4.5.0正式版/lodash.src.js#L5931 "View in source.") + [npm](https://www.npmjs.com/package/lodash.flatten "See the npm package.") ``` _.flatten(array) ``` 向上一级展平数组嵌套 ### 参数 1. array (Array) 需要展平的数组 ### 返回值 (Array) 返回展平后的新数组 ### 示例 ``` _.flatten([1, [2, [3, [4]], 5]]); // => [1, 2, [3, [4]], 5] ```