how to create enum values with es6 in node js?

user_13067435 0
Viewed 4105

Is it possible to create enum values in JavaScript and assign them to integer values, similar to other languages. For example in C#, I declare an enum in the following way: 

enum WeekDays
{
    Monday = 0,
    Tuesday =1,
    Wednesday = 2,
    Thursday = 3,
    Friday = 4,
    Saturday =5,
    Sunday = 6
}
node.js javascript
4 Answers

You can use object as an enum after freezing it like example below:

const WeekDays = Object.freeze({
  Monday: 0,
  Tuesday: 1,
  Wednesday: 2,
  Thursday: 3,
  Friday: 4,
  Saturday: 5,
  Sunday: 6
})
user_126377050

You can create a simple object and export it via module.exports:

// days.js
module.exports = {
  Monday: 0,
  Tuesday: 1,
  Wednesday: 2,
  Thursday: 3,
  Friday: 4,
  Saturday: 5,
  Sunday: 6
}

// file-where-you-want-to-use.js
const DAYS = require('./days.js');
console.log(DAYS.Monday);
user_23576330

You can use a plain old object: 

const WeekDays = {
    Monday: 0,
    Tuesday: 1,
    Wednesday: 2,
    Thursday: 3,
    Friday: 4,
    Saturday: 5,
    Sunday: 6
}

const day1 = WeekDays.Monday;
const day2 = WeekDays.Tuesday;

console.log(day1, day2, day1 === day2);
console.log(day1 === WeekDays.Monday, day2 === WeekDays.Tuesday);

user_62248230

To add some sort of variables that you'd like to use:

// days.js
module.exports = {
  Monday: 0,
  Tuesday: 1,
  Wednesday: 2,
  Thursday: 3,
  Friday: 4,
  Saturday: 5,
  Sunday: 6
}

// file-where-you-want-to-use.js
const DAYS = require('./days.js');
const firstDayOfWeek = 'Monday';

console.log((DAYS)[firstDayOfWeek]);   // 0
user_71327740
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