封闭、冻结对象API

const user={
    name:"hundsun",
    age:16
}

console.log(Object.isSealed(user));//判断对象是否被封闭
Object.seal(user);//封闭对象API

console.log(Object.isSealed(user));

Object.freeze(user);//冻结对象
console.log(Object.isFrozen(user));