js map()初步学习

let data = [3,4,2];
    let data2 = data.map(item=>{
    return item*5
})
console.log(data2)

let users = [
    {name: "天海佑希", "email": "zhang@email.com"},
    {name: "麻乃佳世", "email": "jiang@email.com"},
    {name: "天上欧蒂娜", "email": "li@email.com"}
];
let emails = users.map(item=>item.email)

let data3 = data.map(parseInt)
console.log(data3) //[3,NaN,NaN]