ES6 單個數組內對象去重

去重Set

const arr = ['張三','張三','三張三'] let set = new Set(arr); // set 自帶去重 // Set { '張三', '三張三' } console.log(set); console.error(Array.from(set)); // [ '張三', '三張三' ] 

可直接在控制台粘貼打印 f12

let person = [ {id: 0, name: "小明"}, {id: 1, name: "小張"}, {id: 2, name: "小李"}, {id: 3, name: "小孫"}, {id: 1, name: "小周"}, {id: 2, name: "小陳"}, ]; let obj = {}; let peon = person.reduce((cur,next) => { obj[next.id] ? "" : obj[next.id] = true && cur.push(next); return cur; },[]) //設置cur默認類型為數組，並且初始值為空的數組 console.log(peon); // (4) [{…}, {…}, {…}, {…}]0: {id: 0, name: "小明"}1: {id: 1, name: "小張"}2: {id: 2, name: "小李"}3: {id: 3, name: "小孫"}length: 4__proto__: Array(0) 

去重reduce

let hash = {};
let config = [{
    name: 2,
    state: true,
    output: 'Y',
}, {
    name: 3,
    state: true,
    output: 'A',
}, {
    name: 5,
    state: true,
    output: 'S',
}, {
    name: 7,
    state: true,
    output: 'B',
}];

config = [...config, {
    name: 3,
    state: false,
    output: 'A',
}]
const newArr = config.reduceRight((item, next) => { hash[next.name] ? '' : hash[next.name] = true && item.push(next); return item }, []);
console.log(JSON.stringify(newArr));

// [{"name":3,"state":false,"output":"A"},{"name":7,"state":true,"output":"B"},{"name":5,"state":true,"output":"S"},{"name":2,"state":true,"output":"Y"}]

擴展

js 刪除兩個數組中id相同的對象