It was always complicated to flatten an array in JS. Not anymore! ES2019 introduced a new method that flattens arrays with Array.flat()...
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/flatMap varnew_array = arr.flatMap(functioncallback(currentValue[, index[, array]]) {// return element for new_array}[, thisArg]) flat https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/G...
flat() is a new array instance method that can create a one-dimensional array from a multidimensional array.Example:['Dog', ['Sheep', 'Wolf']].flat() //[ 'Dog', 'Sheep', 'Wolf' ]By default it only “flats” up to one level....
These methods are fairly new and only works in the latest versions of modern browsers, and Node.js 11 and higher.The Array.flat() method creates a new array with all sub-array elements concatenated into it recursively up to the specified depth:...
Home Question Build tree array from flat array in javascript I wrote an ES6 version based on @Halcyon answer const array = [ { id: '12', parentId: '0', text: 'one-1' }, { id: '6', parentId: '12', text: 'one-1-6' }, { id: '7', parentId: '12', text: 'one-1-7...
Theflat()method concatenates sub-array elements. See Also: The Array map() Method The Array flatMap() Method The Array filter() Method The Array forEach() Method Syntax array.flat(depth) Parameters ParameterDescription depthOptional. How deep a nested array should be flattened. ...
flatMap flatMap > flat + map https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/flatMap varnew_array=arr.flatMap(functioncallback(currentValue[,index[,array]]){ // return element for new_array }[,thisArg]) ...
一、功能概述 1、Object.fromEntries 将二维数组或者map转换成对象; 2、trimStart 和 trimEnd 去除字符串前后的空白字符; 3、Array.prototype.flat 与 flatMap 将多维数组降维; 4、Symbol.prototype.description 获取Symbol的字符串描述; 二、Object.fromEntries ...
console.log(arr.flat()) // [0, 1, 2, 3, [4, 5], 6] console.log(arr.flat(Infinity)) 数组去重 一、利用ES6中的 Set 方法去重 注:Set为ES6新增的一个对象,允许存储任何类型(原始值或引用值)的唯一值 console.log(...new Set(arr)); // [1,0,2,9,8,3] ...
js array flat all in one array flat flatMap flatMap > flat + map var new_array = arr.flatMap(function callback(currentValue[, index[, array]]) { // return element for new_array }[, thisArg]) 1. 2. 3. flat var newArray = arr.flat([depth]); ...