In this article we will learn how to add an element to a set.
It is very common to add an element to a set in JavaScript.
Problem
Now we have a problem, which is that we want to add an element to a set.
Now let's imagine we have a set like this:
// Set
[1, 2, 3, 4]
And we want to add new element to this set, to become like this:
[1, 2, 3, 4, 5]
How to solve this problem?
Fortunately, we have a built-in function that add elements to set called add
.
Add an elements to a set using add
We can use add
method to add an element to a set.
For Example
// set
const set = new Set([1, 2, 3, 4]);
// Before adding element
console.log(set);
// Add element
set.add(5);
// After adding element
console.log(set);
Output
Set(5) { 1, 2, 3, 4, 5 }
You should know you can chain multiple calls together.
// set
const set = new Set([1, 2, 3, 4]);
// Chaining elements
set.add(5)
.add(6)
.add(7)
.add(8)
// Result:
console.log(set);
Output
Set(8) { 1, 2, 3, 4, 5, 6, 7, 8 }
The keys in the set are unique, and this means that if you use more than one element with the same value, only one element will be added (last one)
// set
const set = new Set([1, 2, 3, 4]);
// Chaining elements
set.add(5).add(5).add(5);
// After adding element
console.log(set);
Output
Set(5) { 1, 2, 3, 4, 5 }
As you noticed, the country field has been updated.
Thank you for reading
Thank you for reading my blog. 🚀