兩個數組對象取並集

兩個數組對象去並集

arr1中的每一項都是對象,arr2中的每一項也都是對象

const a = [
    {_id: 1},
    {_id: 2},
    {_id: 3},
];
const b = [
    {_id: 2},
    {_id: 4},
]

解決方法一:

const c = a.filter(x => !b.find(y => y._id === x._id)); // [ { _id: 1 }, { _id: 3} ]

解決方法二:

const c = a.filter(x => b.every(y => y._id !== x._id));