小编Dew*_*awa的帖子

var mySelf = {
  name: "dina",
  job: "Programmer",
  yearOfBirth: 1993,
  age: () => 2019 - this.yearOfBirth
};

let result = mySelf.age();

console.log(result);

结果是 NaN

请帮帮我实际发生了什么？