No this for Arrow function

by fredericklim

HTML

<p id='a'></p>
<a id='b'></a>
<a id='c'></a>

JavaScript

document.getElementById('a').innerHTML = "Demo";

let user = {
   firstName: "Ilya",
   lastName: "A",
   sayHi() {
      let arrow = () => document.getElementById('a').innerHTML = this.firstName;
      arrow();
   },
   sayHello() {
      let funexp = function () {
         document.getElementById('c').innerHTML = this.lastName;
      }
      funexp();
   }
};

user.sayHi(); // Ilya
user.sayHello();