JavaScript实现数组对象去重的多种方法

Array.from(new Set(array))

const arr = [
    { id: 1, name: 'A' },
    { id: 2, name: 'B' },
    { id: 1, name: 'A' },
    { id: 3, name: 'C' }
];

const result = Array.from(new Set(arr.map(item => JSON.stringify(item)))).map(item => JSON.parse(item));
console.log(result);

const arr = [
    { id: 1, name: 'A' },
    { id: 2, name: 'B' },
    { id: 1, name: 'A' },
    { id: 3, name: 'C' }
];
const result = arr.reduce((pre, cur) => {
    var exists = pre.find(item => JSON.stringify(item) === JSON.stringify(cur));
    if (!exists) {
        pre.push(cur);
    }
    return pre;
}, []);
console.log(result);

const arr = [
    { id: 1, name: 'A' },
    { id: 2, name: 'B' },
    { id: 1, name: 'A' },
    { id: 3, name: 'C' }
];
const result =arr.filter((item, index, self) => {
    return self.findIndex(t => JSON.stringify(t) === JSON.stringify(item)) === index;
});
console.log(result);

//reduce第一个参数是遍历需要执行的函数，第二个参数是item的初始值
var arr = [{"id":1,"name":"张三"},{"id":2,"name":"李四"},{"id":3,"name":"王五"},{"id":2,"name":"张三"}];
var obj = {};
arr = arr.reduce(function(item, next) {
       obj[next.id] ? '' : obj[next.id] = true && item.push(next);
       return item;
    }, []);
console.log(arr);

var arr2 = [{"id":1,"name":"张三"},{"id":2,"name":"李四"},{"id":3,"name":"王五"},{"id":2,"name":"张三"},{'id':4,'name':'李四'}];

function unique(arr){
    const res= new Map()
    return arr.filter((a)=> !res.has(a.id) && res.set(a.id,1) && !res.has(a.name) && res.set(a.name,1))
}
//输出结果：
unique(arr2)
[
    {
        "id": 1,
        "name": "张三"
    },
    {
        "id": 2,
        "name": "李四"
    },
    {
        "id": 3,
        "name": "王五"
    }
]