SOURCE

let objValue = {}

console.log(JSON.stringify(objValue)==='{}')

let result = function (obj) {
  for (let key in obj) {
    return false;//如果不为空，可遍历，返回 false
  }
  return true;
}
console.log(result(objValue));//返回true

console.log(Object.keys(objValue).length == 0);//返回true