解構指派(es6)

let person={
    name:"張三",
    age：20
}

let {name,age,city="北京"}=person
console.log(name,age)

//或者
let name,age
({name,age}=person)
console.log(name,age)

//取别名
let {name：Pname,age,city="北京"}=person
           

深層嵌套

let person={
    children:{
        name:"張三",
        age：20
    }
}
           

let book=['PHP,'JAVA',['javascript','css','html']]
let [a,,[,,j]]=book
console.log(a,j)

let [a,,[...html]]=book
console.log(a,html[1])

let [...newBooks]=book
console.log(..newBooks)