ES6 数组中的对象去重

 用set 去重

let person = [
     {id: 0, name: "小明"},
     {id: 1, name: "小张"},
     {id: 2, name: "小李"},
     {id: 3, name: "小孙"},
     {id: 1, name: "小周"},
     {id: 2, name: "小陈"},   
];

let obj = {};

let peon = person.reduce((cur,next) => {
    obj[next.id] ? "" : obj[next.id] = true && cur.push(next);
    return cur;
},[]) //设置cur默认类型为数组，并且初始值为空的数组

console.log(peon);

打印结果：
[
    {id: 0, name: "小明"}
    {id: 1, name: "小张"}
    {id: 2, name: "小李"}
    {id: 3, name: "小孙"}
]

 用reduce去重

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"}]

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