How to create a function that invokes the method at a given key of an object in JavaScript ?

How to create a new object from the specified object, where all the keys are in lowercase in JavaScript?

Last Updated : 17 Feb, 2023

In this article, we will learn how to make a new object from the specified object where all the keys are in lowercase using JavaScript.

Example: Here, we have converted the upper case to lower case key values.

Input: {RollNo : 1, Mark : 78}

Output: {rollno : 1, mark : 78}

Approach 1: A simple approach is to Extract keys from Object and LowerCase to all keys and make Object with them. For this purpose we use Object.keys( ) to extract keys from the object. And use String.toLowerCase() method to lower case keys and Array.reduce() method to make an object with lower-case strings.

Example: This example shows the above-explained approach.

Javascript

// Test Object 
const Student = { RollNo : 1, Mark: 78 }; 
  
// Function to lowercase keys  
function Conv( obj , key ) 
{ 
  obj[key.toLowerCase()] = Student[key]; 
  return Student; 
} 
  
// Function to  create object from lowercase keys  
function ObjKeys( obj) { 
  let arr1 = Object.keys(obj); 
  let ans = {}; 
  for(let i of arr1) 
  { 
  Conv(ans,i); 
  
  } 
  return ans; 
} 
  
a = ObjKeys(Student); 
console.log(a);

Output:

{ rollno : 1, mark : 78}

Approach 2: The simplest approach is to convert the Object to an array and make keys lowercase and make objects from a new array. For this purpose, we use Object.entries() to make an array from Object. And we use Array.map() to apply String.toLowerCase() method to all keys. To convert a new array to an Object we use Object.fromEntries().

Example: This example shows the above-explained approach.

Javascript

// Test Object 
const employ = { EmpId: 101, Batch: 56 }; 
  
// Converting Object to array  
let k = Object.entries(employ); 
  
//  Apply toLowerCase function to all keys  
let l = k.map(function(t){ 
  t[0] = t[0].toLowerCase() 
  return t; 
  } 
); 
  
// Converting back array to Object 
const a  = Object.fromEntries(l) 
console.log(a)

Output:

{ empid : 101, batch : 56 }

How to create a function that invokes the method at a given key of an object in JavaScript ?

S

satyam00so

Improve

Article Tags :

Similar Reads

How to Create Array of Objects From Keys & Values of Another Object in JavaScript ?

Creating an array of objects from the keys and values of another object involves transforming the key-value pairs of the original object into individual objects within an array. Each object in the array represents a key-value pair from the source object. Below approaches can be used to accomplish th

How to create a function that invokes the method at a given key of an object in JavaScript ?

In JavaScript objects store variables in the key-value pair where the key is the property of the object and the value maybe the value of the property, or it may be any method that invokes when it is called. In this article, we will learn to invoke a method that is provided to key. Approach: Generall

How to loop through a plain object with the objects as members in JavaScript ?

Looping through a plain JavaScript object with objects as members means iterating over each property of the object and accessing its values, which may also be objects. This is a common task in JavaScript, especially when dealing with JSON data or APIs. There are several ways to loop through a plain

How to check if the provided value is an object created by the Object constructor in JavaScript ?

In this article, we will learn how to check if the provided value is an object created by the Object constructor in JavaScript. Almost all the values in JavaScript are objects except primitive values. There are several methods that can be used to check if the provided value is an object created by t

How to Remove a Property from All Objects in an Array in JavaScript?

To remove a property from all objects in an array in JavaScript, you can use the forEach() method to iterate over each object in the array and use the delete operator to remove the specified property. Example:[GFGTABS] JavaScript const arrayOfObjects = [ { name: "Alice", age: 25, city:

How to replace lowercase letters with an other character in JavaScript ?

Given a string and the task is to replace all lowercase letters from a string with the other characters in JavaScript. There are some approaches to replace the character that are described below: JavaScript replace() Method: This method searches a string for a defined value, or a regular expression,

How to get all property values of a JavaScript Object (without knowing the keys) ?

To get all property values from a JavaScript object without knowing the keys involves accessing the object's properties and extracting their values. Below are the approaches to get all property values of a JavaScript Object: Table of Content Using Object.values() MethodUsing Object.keys() methodAppr

How to access an object having spaces in the object's key using JavaScript ?

Given an object and the task is to access the object in which the key contains spaces. There are a few methods to solve this problem which are discussed below: Approach 1: Create an object having space-separated keys.Use square bracket notation instead of dot notation to access the property. Example

How to use a variable for a key in a JavaScript object literal?

Using a variable as a key in a JavaScript object literal enables dynamic property creation, allowing us to define object properties based on variable values. Syntax: let key="your_choice";let object = {};object[key] = "your_choice";console.log(object);Example: This shows how to use a variable for a

How to Create an Array of Object Literals in a Loop using JavaScript?

Creating arrays of object literals is a very frequent activity in JavaScript, as often when working with data structures, several objects are needed. This article will allow your hand through different ways of coming up with an array of object literals in a loop in JavaScript. Here are different app