JavaScript Enum

In JavaScript, a fixed collection of named values is represented via enums. They enable programmers to create a list of named constants that may be used across the codebase to improve error prevention, readability, and maintainability.

Enumerations, often known as enums, are used in JavaScript to express a fixed collection of named values. Since enums are not built into JavaScript, objects or frozen arrays are typically used to implement them.

Weekdays such as {"SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, and SATURDAY",} colors like {"BLUE, RED, YELLOW, PINK, GREEN"} etc., seasons like {"SUMMER, AUTUMN or FALL, SPRING, WINTER"}, and directions like {"EAST, WEST, NORTH, SOUTH, NORTH EAST, SOUTH EAST, and SOUTH WEST"} can all be included in this enum.

Does Enum Support JavaScript?

JavaScript lacks an integrated enum data type, even though enum data types are often used in many computer languages, including C++, Java, etc. Classes and objects may be used to implement Enum's features in JavaScript.

Syntax:

Let us see one example, where we are using enum types with integer values in our JavaScript code.

Output:

Small codebases can use this approach, albeit in some circumstances it can lead to ambiguity. The developer may write the instruction in the following example, as an illustration of the first letter in lowercase, but the string matching fails and returns false.

Output:

Because they are only two values of a basic type, developers may also design unrelated enums that conditional operators mistakenly match. Let's examine this issue with an example.

Output:

In this example, two distinct enum types are formed, but they get jumbled up during the if block's value check. We want something else. Furthermore, it is logically wrong to use integers or numbers. Directions, for instance, need to have their kinds represented more effectively because they are neither strings nor integers nor numbers.

Enums with Symbol types

A notion in JavaScript is known as Symbol(). Symbols don't run into each other. Therefore, it will be more suitable and less error-prone to specify values using symbols. Below is the syntax.

Syntax:

Let's look at a comparable case where symbols are utilized and determine if they collide or not.

Output:

Creating Immutable Enum types

Few enumeration implementations have been found thus far. However, there are a few issues. We may update the value of an enum type in the final strategy as well by just giving it a new value. Enum updates can be limited by making it immutable by sending the object through the Object.freeze() function. Let's use this as an illustration.

Syntax:

Example

Output:

In summary

To make our program easier to read, we may employ an ordered collection of constants created using the enumerated or enum datatypes. JavaScript does not handle enumerated types natively, in contrast to other languages. Enums may be designed in a variety of ways for our JavaScript programs. The fundamental enums can be created by objects with integer or string values; however, this approach is not appropriate in many situations, as two enums of the same type may conflict. Using symbols to prevent the collision is one potential option. Using classes as enum types is the most suitable way to make our enums immutable so that we can prevent needless modifications.