How to define integer constants in JavaScript?

ECMAScript allows usage of const to define constants in JavaScript. To define integer constants in JavaScript, use the const keyword.

Syntax

const CONSTANT_NAME = value;

Example

const MY_VAL = 5;
console.log("MY_VAL:", MY_VAL);

// This will throw an error
try {
    MY_VAL = 10;
} catch (error) {
    console.log("Error:", error.message);
}

MY_VAL: 5
Error: Assignment to constant variable.

Key Points

As shown above, MY_VAL is a constant with value 5 assigned. Attempting to reassign another value to a constant variable throws an error.

Using const will not allow you to reassign any value to MY_VAL again. If you assign a new value to a constant, it leads to a TypeError.

Multiple Integer Constants

const MAX_SIZE = 100;
const MIN_SIZE = 1;
const DEFAULT_COUNT = 50;

console.log("MAX_SIZE:", MAX_SIZE);
console.log("MIN_SIZE:", MIN_SIZE);
console.log("DEFAULT_COUNT:", DEFAULT_COUNT);

MAX_SIZE: 100
MIN_SIZE: 1
DEFAULT_COUNT: 50

Conclusion

Use const to define integer constants in JavaScript. Once declared, constant values cannot be reassigned, making your code safer and more predictable.