How to use the map() method In Javascript
By using the map() method we can create an array of partial objects from another object’s array. The map() method takes the keys of the object array as the parameters which are required to be in the desired object array and returns the key-value pairs of that particular key. In the below example, we obtain the key-value pairs of the name and age as the array of partial objects of which the parameters are given in the map method.
Syntax:
partialObjectArray = ObjectArray.map((
{key 1, key 2, ...key n}) => ({key 1, key 2, ...key n}));
Note: key 1, key 2, …key n are the fields that are needed in the partial object array
Example: This is the illustration of creating an array of partial objects from another array using the map() method.
let = studentDetails = [
{
name: 'dinesh',
age: 20,
marks: 30,
Grade: 'F'
},
{
name: 'divi',
age: 20,
marks: 60,
Grade: 'B'
},
{
name: 'vignesh',
age: 30,
marks: 80,
Grade: 'A'
}]
let partialStudentDetails = studentDetails.map((
{ name, age, Grade }) => ({ name, age, Grade }));
console.log(partialStudentDetails);
Output
[ { name: 'dinesh', age: 20, Grade: 'F' }, { name: 'divi', age: 20, Grade: 'B' }, { name: 'vignesh', age: 30, Grade: 'A' } ]
How to create an array of partial objects from another array in JavaScript ?
Creating an array of partial objects from another array is a useful technique in JavaScript, especially for data transformation and manipulation. This guide covers various methods to efficiently create these arrays, enhancing your ability to work with complex data structures.
Importance of Creating Partial Objects:
Creating partial objects is crucial for:
- Simplifying data structures for specific use cases.
- Improving performance by reducing the size of data handled.
- Enhancing readability and maintainability of code by focusing on relevant properties.
These are some common methods:
Table of Content
- Using the map() method
- Using Destructuring
- Using reduce Method()
- Using forEach() method
- Using a for Loop