How to use Object Literal with Object.freeze() In Javascript
In this approach, we are using Object.freeze() method. Let’s consider the sizes of a T-shirt: Small, Medium, Large and Extra Large. Now let’s create an object which represents this available T-shirt sizes and then freeze it using Object.freeze(). This method freezes an object, preventing any additions, deletions, or modifications to its properties.
Example: This example shows the creation of enums using Object.freeze() method.
const TShirtSizes = Object.freeze({
SMALL: 'S',
MEDIUM: 'M',
LARGE: 'L',
EXTRA_LARGE: 'XL'
});
console.log(TShirtSizes.MEDIUM);
Output
M
Note: If we try to change the TShirtSizes object then it will throw TypeError, because we had enabled Strict mode.
"use strict"; // strict mode is on
const TShirtSizes = Object.freeze({
SMALL: 'S',
MEDIUM: 'M',
LARGE: 'L',
EXTRA_LARGE: 'XL'
});
// Trying to modify a frozen
// object but it will throws an error
TShirtSizes.EXTRA_LARGE = 'XXL';
Output: As demonstrated earlier, attempting to modify the enum after freezing it results in no change, but if strict mode is enabled, it will throw a TypeError.
Note: It’s a common convention in many programming languages, including JavaScript, to write enum constants in all capital letters to distinguish them from other variables and constants.
How to Create Enums in JavaScript ?
An enum, short for “enumerated type”, is a special data type in programming languages that allows us to define a set of named constants. These constants are essentially unchangeable variables that represent a fixed collection of possible values. Each contants can be accessed by its name. Enums are very similar to constants but they offer more data structure. we will learn about creating enums in JavaScript, exploring their significance in code organization and readability, along with practical implementation approaches using closures and other techniques.
These are the following approaches:
Table of Content
- Using Object Literal with Object.freeze()
- Using ES6 Symbols
- Using Closures