How to define an "enumeration" type in JS

Javascript1.8.5 You can use Object.freeze To freeze objects to implement a similar ” enumeration ” type .

The implementation code is as follows ：

/**
 *  Time ：2019 year 8 month 18 Japan 
 *  Front end tutorial ： https://www.pipipi.net/ 
 */
var DaysEnum = Object.freeze({"monday":1, "tuesday":2, "wednesday":3, ...})

Or so ：

/**
 *  Time ：2019 year 8 month 18 Japan 
 *  Front end tutorial ： https://www.pipipi.net/ 
 */
var DaysEnum = {"monday":1, "tuesday":2, "wednesday":3, ...}
Object.freeze(DaysEnum)

This is it. js Medium ” enumeration ”！ Is it simple ？

But now it's 2019 Years. , We can also use const To define the object .

Complete code

The complete implementation code is as follows ：

/**
 *  Time ：2019 year 8 month 18 Japan 
 *  Front end tutorial ： https://www.pipipi.net/ 
 */
var Status = Object.freeze({
    "Connecting":0,
    "Ready":1,
    "Loading":2,
    "Processing": 3
});

console.log(Status.Ready) // 1

console.log(Object.keys(Status)[Status.Ready]) // Ready