const superman = {
name : 'clark',
age : 30,
}
superman.haircolor="black"; // 추가
superman('hobby') = 'football'; // 추가
console.log(superman.name)
delete superman.age;
console.log(superman)
function makeObject(name, age){
return{
name : name, // name으로 축약가능
age : age, / age로 축약가능
hobby : 'football'
}
}
const Mike = makeObject('Mike', 30)
console.log(Mike);
console.log('age' in Mike) // true
console.log('birthday' in Mike) //false
function isAdult(user){
if(!
('age' in user) || // user에 age가 없거나
user.age <20) { // 20살 미만이거나
return false;
}
return true;
}
const Mike = {
name : "Mike",
age : 30
};
const Jane = {
name: "Jane"
}
console.log(isAdult(Mike)) // true
console.log(isAdult(Jane)) /// false
const Mike = {
name : "Mike",
age : 30
};
for (x in Mike)
console.log(x) // name, age가 찍힘
const Mike = {
name : "Mike",
age : 30
};
for (x in Mike){
console.log(Mike(x)) // Mike('name') 돌고 그다음 Mike('age')
}