1、给json中添加元素

    let obj = {name:"张三",age:18};
    obj.sex = "男";
    console.log(obj);

2、对比两个数组，取出来相同的元素

    let arr1 = [0,1,2,3,4,5];
    let arr2 = [0,4,6,1,3,9];
    function getArrEqual(arr1, arr2) {
        let newArr = [];
        for (let i = 0; i < arr2.length; i++) {
            for (let j = 0; j < arr1.length; j++) {
                if(arr1[j] === arr2[i]){
                    newArr.push(arr1[j]);
                }
            }
        }
        return newArr;
    }
    console.log(getArrEqual(arr1, arr2));