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JavaScript: Create a new object from the specified object, where all the keys are in lowercase

JavaScript fundamental (ES6 Syntax): Exercise-180 with Solution

Write a JavaScript program to create a new object from the specified object, where all the keys are in lowercase.

  • Use Object.keys() and Array.prototype.reduce() to create a new object from the specified object.
  • Convert each key in the original object to lowercase, using String.prototype.toLowerCase().

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const lowercaseKeys = obj =>
  Object.keys(obj).reduce((acc, key) => {
    acc[key.toLowerCase()] = obj[key];
    return acc;
  }, {});
const myObj = { Name: 'Adam', sUrnAME: 'Smith' };
const myObjLower = lowercaseKeys(myObj);
console.log(myObjLower);

Sample Output:

{"name":"Adam","surname":"Smith"}

Pictorial Presentation:

JavaScript Fundamental: Create a new object from the specified object, where all the keys are in lowercase.

Flowchart:

flowchart: Create a new object from the specified object, where all the keys are in lowercase

Live Demo:

See the Pen javascript-basic-exercise-180-1 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

How to check whether a string contains a substring in JavaScript?

ECMAScript 6 introduced String.prototype.includes:

const string = "foo";
const substring = "oo";

console.log(string.includes(substring));

includes doesn't have Internet Explorer support, though. In ECMAScript 5 or older environments, use String.prototype.indexOf, which returns -1 when a substring cannot be found:

var string = "foo";
var substring = "oo";

console.log(string.indexOf(substring) !== -1);

Ref: https://bit.ly/3fFFgZv