객체 메소드 ( Object methods )

Object.assign() : 객체 복제

const user = {name : 'Mike', age : 30 }

const newUser = Object.assign({}, user);

console.log(newUser);

>> {
  "name": "Mike",
  "age": 30
   }

Object.keys() : 키 배열 반환

const user = { name : 'Mike', age : 30, gender : 'male' }

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

>> ["name","age","gender"]

Object.values() : 값 배열 반환

const user = { name : 'Mike', age : 30, gender : 'male' }

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

>> ['Mike', 30, 'male']

Object.entries() : 키, 값 배열 반환

const user = { name : 'Mike', age : 30, gender : 'male' }

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

>>  ['name', 'Mike'], ['age', 30], ['gender', 'male']

Object.fromEntries(): 키, 값 배열을 객체로

const arr = [ ['name', 'Mike'], ['age', 30], ['gender', 'male'] ];

console.log( Object.fromEntries(arr) );

>> { "name": "Mike", "age": 30," gender": "male" }