Javascript Tip #3 - Class private properties and methods

js-tip3.js

/* Tweet: https://twitter.com/AnsonH_/status/1435945599367479303 */

class Student {
  #gpa; // 1. Declare private property using the # sign

  constructor(gpa) {
    this.#gpa = gpa; // 2. Add this private property to class instance
  }
  
  // Private method
  #setGpa(newGpa) {
    this.#gpa = newGpa;
  }
}

const tom = new Student(2.0);

console.log(tom); // undefined (since tom.gpa is private field)
tom.gpa = 4.3; // tom's private gpa property will not change

tom.setGpa(4.3); // TypeError: tom.setGpa is not a function