8、for of (在 ES6 中引入的 for...of 循环,以替代for...in和forEach(),并支持新的迭代协议。 for...of 允许你遍历 Arrays(数组), Strings(字符串), Maps(映射), Sets(集合) 等可迭代的数据结构等(不包括对象))。 // 字符串 let str = "hello"; for (let s of str) { console.log(s); ...
for...of允许遍历 Arrays(数组), Strings(字符串), Maps(映射), Sets(集合)等可迭代的数据结构等。 语法: for (var item of iterable) { 执行的代码块 } 其中两个参数: item:每个迭代的属性值被分配给该变量。 iterable:一个具有可枚举属性并且可以迭代的对象。 该方法允许获取对象的键值: var arr = [...
1 Sort a javascript array into nested arrays based on values 1 How to sort a multi-dimensional array in javascript 0 Order/Sort array map items based on the specific value retaining actual order for rest of the items in javascript Hot Network Questions Preventing duplicate curve ...
for of 允许你遍历 Arrays(数组), Strings(字符串), Maps(映射), Sets(集合)等可迭代的数据结构等。 循环一个数组: let arr = ['A', 'B', 'C']for(let val of arr) { console.log(val) }//A B C循环一个字符串: let iterable= "abc";for(let value of iterable) { console.log(value);...
I'm trying to .map() an object of arrays to create a div for each key/value pair. Here is a sample of the object format:const data = { year: ["2018", "2020"], make: ["Honda"], model: ["Accord", "Civic"], subModel: [] } ...
Return a new array with the square root of all element values: constnumbers = [4,9,16,25]; constnewArr = numbers.map(Math.sqrt) Try it Yourself » Multiply all the values in an array with 10: constnumbers = [65,44,12,4]; ...
for ··· in ··· / for ··· of ··· for...in语句以任意顺序遍历一个对象的可枚举属性。对于每个不同的属性,语句都会被执行。每次迭代时,分配的是属性名 补充: 因为迭代的顺序是依赖于执行环境的,所以数组遍历不一定按次序访问元素。 因此当迭代那些访问次序重要的 arrays 时用整数索引去进行for循...
for...of语句在可迭代对象(包括 Array,Map,Set,String,TypedArray,arguments 对象等等)上创建一个迭代循环,调用自定义迭代钩子,并为每个不同属性的值执行语句。 代码语言:txt 复制 const array = ['a', 'b', 'c']; for (const element of array) { ...
A Map remembers the original insertion order of the keys. Example // Create a Map constfruits =newMap([ ["apples",500], ["bananas",300], ["oranges",200] ]); Try it Yourself » Map Methods and Properties MethodDescription new Map()Creates a new Map object ...
In the example, we turn the map into arrays. let stones2d = Array.from(stones); We create a 2D array from thestonesmap. Each subarray is a pair from the map. let keys = Array.from(stones.keys()); We create an array of map keys. ...