属性名的遍历

Object.getOwnPropertySymbols()

const obj = {}
let a = Symbol('a')
let b = Symbol('b')

obj[a] = 'Hello'
obj[b] = 'World'

const objectSymbolsProperties = Object.getOwnPropertySymbols(obj)

objectSymbolsProperties // [Symbol(a), Symbol(b)]

Reflect.ownKeys()

let obj = {
  [Symbol('my_key')] : 1,
  enum: 2,
  nonEnum: 3
}

Reflect.ownKeys(obj)
// ["enum", "nonEnum", Symbol(my_key)