SOURCE

const obj = { a: 100, b: 200 }
console.log('a' in obj)
console.log(obj)

console.log(Reflect.has(obj, 'a'))

console.log('')

const obj2 = { a: 1000, b: 2000 }
delete obj2.a
console.log(obj2)

console.log('')

const obj3 = { a: 10000, b: 10000 }
Reflect.deleteProperty(obj3, 'b')
console.log(obj3)

console.log('')

let obj4 = {}
obj4.a = '你好'
obj4.b = '您好'
console.log(Object.getOwnPropertyNames(obj4))
console.log(Reflect.ownKeys(obj4))

console.log('Object.getOwnPropertyDescriptor() 方法返回指定对象上一个自有属性对应的属性描述符。（自有属性指的是直接赋予该对象的属性，不需要从原型链上进行查找的属性）')
console.log(Object.getOwnPropertyDescriptor(obj4, 'a'))
console.log('')
console.log('Object.getOwnPropertySymbols() 方法返回一个给定对象自身的所有 Symbol 属性的数组。')
console.log(Object.getOwnPropertySymbols(obj4))
console.log('')
console.log('Object.getPrototypeOf() 方法返回指定对象的原型（内部[[Prototype]]属性的值）。')
console.log(Object.getPrototypeOf(obj4))