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How to Convert an Array to an Object in JavaScript – Top JavaScript Interview Questions for React.js and JavaScript Developers

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Convert ARRAY to OBJECT in javascript

Convert ARRAY to OBJECT in javascript

If you’re a JavaScript developer or someone who’s looking to improve their skills, you’ve probably come across the need to convert an array to an object at some point. In this article, we’ll discuss how to achieve this in JavaScript and why it’s a useful skill to have in your toolbox.

What is an array and an object in JavaScript?

Before we dive into the conversion process, let’s briefly define what an array and an object are in JavaScript. An array is a data structure that stores a collection of elements, typically of the same type. It is indexed and can be accessed using numerical indices. On the other hand, an object is a collection of key-value pairs, where each key is a unique identifier for a value.

Converting an array to an object

One common scenario where you might need to convert an array to an object is when you have an array of items and want to create a lookup table for efficient value retrieval. This is where the Array.reduce() method comes in handy.

Here’s a simple example of how to convert an array to an object using the reduce method:

“`javascript
const arr = [
{ id: 1, name: ‘Alice’ },
{ id: 2, name: ‘Bob’ },
{ id: 3, name: ‘Charlie’ }
];

const obj = arr.reduce((acc, cur) => {
acc[cur.id] = cur;
return acc;
}, {});

console.log(obj);
“`

In this example, we start with an empty object as the initial value for the accumulator. We then loop through each item in the array and assign the item to the object using its id as the key. After the reduce operation is completed, we get an object with the ids as keys and the corresponding items as values.

Why is this useful?

Converting an array to an object can be a useful technique in a variety of scenarios. For example, you may want to quickly look up items based on a unique identifier without having to iterate through the entire array each time. This can improve the performance of your code, especially when dealing with large datasets.

Additionally, many JavaScript libraries and frameworks, such as React.js, often expect data to be in the form of objects rather than arrays. Being able to convert between these two data structures can make working with these tools much easier.

Conclusion

In conclusion, knowing how to convert an array to an object in JavaScript is a valuable skill that can come in handy in a wide range of scenarios. The Array.reduce() method is a powerful tool that allows you to achieve this conversion with ease. Whether you’re building web applications, working with libraries like React.js, or just looking to improve your JavaScript skills, understanding how to convert between arrays and objects is a useful skill to have in your repertoire.

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@coderdost
10 months ago

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@diveshpatidar5159
10 months ago

Let newArr = […Object.values(obj)];
//['a', 'b', 'c']

@iron_man____
10 months ago

let arr = ['a','b','c']

let obj = arr.reduce((a,it,i)=>{
a[it] = it
return a
},{})
console.log(obj)
//{ a: 'a', b: 'b', c: 'c' }

@AmritpalSingh-sw3bl
10 months ago

Using for each loop we can handle it easily

@killerdroid99
10 months ago

you can use a record for these conversions

@vaxff1945
10 months ago

logic was simple but code should be readabe i was scared after this short later i understood

@ajaypanchal1106
10 months ago

const arr = [1, 23, 4, 56, 7];

// convert it into object

const out = arr.reduce((num, crt, i, ar) => {

return { …num, [crt]: crt };

}, {});

console.log(out);

const rev = Object.values(out).reduce((prev, current, index, arr) => {

return […prev, current];

}, []);

console.log(rev);

@tigerguru2850
10 months ago

Ye konsa theme hai??

@user-tg1wd2xb6j
10 months ago

Aap kaun sa code editor use karte ho. yeah console ki command bhi code mein hi Dikhai ja raha hai ya aap kaise kar rahe ho.
Aap ko subscribe Kar Diya Hai Ab lajmi batana.

@akash.web_dev
10 months ago

const arr=['a','b','c']

let obj = Object.assign({},arr)

console.log(obj);

let array= Object.entries(obj)

console.log(array.flat());

array to object and object to array
ye ek good approch hai ya nahi

@scriptDoodle
10 months ago

Which extension gives results beside code like yours?

@murtazashahidofficial3790
10 months ago

Which code editor is this? Kindly share

@syedjaidahmed1728
10 months ago

Love from Bangladesh

@syedjaidahmed1728
10 months ago

big fan

@vishal10471
10 months ago

Please add some more video in this playlist, please

@webmobi2773
10 months ago

var emptyObj= { }

are.forEach((val)=> {
emptyObj[val] = val;
}

console.log(emptyObj);

🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉

@ayushkamar7100
10 months ago

Ye sir enteries se bi to ho sakta hain ❤❤

@n_fan329
10 months ago

let tab=[]
for (let val in obj){
tab.push(obj[val])
}
console.log(tab2)

@sashirkl
10 months ago

Boss kuch samajh mein nahin aya . And funny part is i know programming. Mujhe kuch knowledge hoke agar samajh nahin aya dusre ko kya aega

@channel6k
10 months ago

let arr=["a","b","c"];
let obj={};

for( let i=0 ;i<arr.length ;i++){
let name=arr[i];
if(obj[name]===undefined){
obj[name]=arr[i]
}

}
console.log(obj) i can do like this ???