This article will show you how to get the first element of a set in JavaScript with three common ways: Using the iterator, destructuring assignment, converting set to array, and using for…of loop. Start reading the detailed article.
How to get the first element of a set in JavaScript
Converting set to array
The easy way is converting the set into the array. Then call the index 0 to get the first element of the array.
Code example:
// Create a new set
const mySet = new Set(['Banana', 'Apple', 'Orange']);
// Convert Set to Array
const getFirstElement = [...mySet][0];
console.log("My Set is : ", mySet);
console.log('The first element of Set is: ', getFirstElement);Output:
My Set is : Set(3) {size: 3, Banana, Apple, Orange}
The first element of Set is: BananaUsing for…of loop
Using for…of the loop is a very common way to get the first element of a set. We loop into all elements in the set. Then call the first element out.
Example:
// Create a new set
const mySet = new Set(['Banana', 'Apple', 'Orange']);
// Create getFirstElement to return the first item of Set
function getFirstElement(set) {
for (let element of set) {
if (element) {
return element;
}
}
return undefined;
}
console.log("My Set is : ", mySet);
console.log('The first element of Set is: ', getFirstElement(mySet));Output:
My Set is : Set(3) {size: 3, Banana, Apple, Orange}
The first element of Set is: BananaDestructuring assignment
The next way is destructuring assignment. This is a direct way to get the first element from a set.
Example:
// Create a new set
const mySet = new Set(['Banana', 'Apple', 'Orange']);
// Only get the first item
const [getFirstElement] = mySet;
console.log("My Set is : ", mySet);
console.log('The first element of the Set is: ', getFirstElement);Output:
My Set is : Set(3) {size: 3, Banana, Apple, Orange}
The first element of the Set is: BananaUsing the iterator
The most practical and elegant solution is using retrieving the first IteratorResult and acquiring its value. We use mySet.keys().next().value.
Example:
// Create a new set
const mySet = new Set(['Banana', 'Apple', 'Orange']);
// Using the iterator
const getFirstElement = mySet.keys().next().value;
console.log("My Set is : ", mySet);
console.log('The first element of the Set is: ', getFirstElement);Output:
My Set is : Set(3) {size: 3, Banana, Apple, Orange}
The first element of the Set is: BananaSummary
Hopefully, throughout these ways outlined above. You can easily find for yourself the best way to get the first element of a set in JavaScript. If you have any problems, please comment below. I will answer as possible. Thanks for your reading!
Maybe you are interested:
- Get the Difference between Two Sets using JavaScript
- How To Merge Sets In JavaScript
- How to get the Union of Two Sets in JavaScript
My name is Fred Hall. My hobby is studying programming languages, which I would like to share with you. Please do not hesitate to contact me if you are having problems learning the computer languages Java, JavaScript, C, C#, Perl, or Python. I will respond to all of your inquiries.
Name of the university: HUSC
Major: IT
Programming Languages: Java, JavaScript, C , C#, Perl, Python
