如何通过比较两个数组；求出两个数组中不同的元素组成新的数组的方法？

Question

arr1=[1,2,4,556,77,89,9];
arr2=[12,12,3,4,5,6,7,87]；
function de(){
//代码
}

Answer 1

arr1 = [1, 2, 4, 556, 77, 89, 9];
arr2 = [12, 12, 3, 4, 5, 6, 7, 87];
let difference = arr1
    .filter(x => arr2.indexOf(x) == -1)
    .concat(arr2.filter(x => arr1.indexOf(x) == -1));
    console.log(difference)

Answer 2

arr1 = [1, 12, 6, 2, 4, 556, 77, 89, 9];
arr2 = [12, 12, 3, 4, 5, 6, 7, 87];

var merge = arr1.concat(arr2).filter(function(v, i, arr) {return arr.indexOf(v) == arr.lastIndexOf(v);});

console.log(merge);