What is the use of the Set object in JavaScript?

The Set object is a built-in object in JavaScript that allows you to store unique values of any type. The values can be primitive types such as strings and numbers, or object references.

To create a new Set object, you can use the Set() constructor:

const mySet = new Set();

You can also pass an iterable object as an argument to the constructor, which will add the values from the iterable to the Set:

const mySet = new Set([1, 2, 3]);

Once you have created a Set, you can add values to it using the add() method:

const mySet = new Set();
mySet.add(1);
mySet.add(2);
mySet.add(3);

You can check if a value is in a Set using the has() method:

const mySet = new Set([1, 2, 3]);
console.log(mySet.has(2)); // true
console.log(mySet.has(4)); // false

You can also remove values from a Set using the delete() method:

const mySet = new Set([1, 2, 3]);
mySet.delete(2);
console.log(mySet.has(2)); // false

You can get the number of values in a Set using the size property:

const mySet = new Set([1, 2, 3]);
console.log(mySet.size); // 3

You can also use the forEach() method to iterate over the values in a Set:

const mySet = new Set([1, 2, 3]);
mySet.forEach((value) => {
  console.log(value);
});

You can use the Set object to remove duplicates from an array.

For example:

const myArray = [1, 2, 2, 3, 3, 3];
const uniqueValues = new Set(myArray);
console.log(uniqueValues); // Set {1, 2, 3}

You can also convert a Set to an array using the spread operator:

const mySet = new Set([1, 2, 3]);
const myArray = [...mySet];
console.log(myArray); // [1, 2, 3]

The Set object also provides several methods for working with sets mathematically.

For example, you can use the union() method to create a new Set that contains all the values from two Sets:

const set1 = new Set([1, 2, 3]);
const set2 = new Set([2, 3, 4]);
const union = new Set([...set1, ...set2]);
console.log(union); // Set {1, 2, 3, 4}

You can use the intersection() method to create a new Set that contains only the values that are in both Sets:

const set1 = new Set([1, 2, 3]);
const set2 = new Set([2, 3, 4]);
const intersection = new Set([...set1].filter((x) => set2.has(x)));
console.log(intersection); // Set {2, 3}

You can use the difference() method to create a new Set that contains only the values that are in the first Set but not the second Set:

const set1 = new Set([1, 2, 3]);
const set2 = new Set([2, 3, 4]);
const difference = new Set([...set1].filter((x) => !set2.has(x)));
console.log(difference); // Set {1}

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