JavaScript: Iterate over all own properties of an object in reverse, running a callback for each one
JavaScript fundamental (ES6 Syntax): Exercise-231 with Solution
Write a JavaScript program to iterate over all the properties of an object in reverse, running a callback for each one.
- Use Object.keys(obj) to get all the properties of the object, Array.prototype.reverse() to reverse their order.
- Use Array.prototype.forEach() to run the provided function for each key-value pair.
- The callback receives three arguments - the value, the key and the object.
Sample Solution:
JavaScript Code:
//#Source https://bit.ly/2neWfJ2
const forOwnRight = (obj, fn) =>
Object.keys(obj)
.reverse()
.forEach(key => fn(obj[key], key, obj));
console.log(forOwnRight({ foo: 'bar', a: 1 }, v => console.log(v)));
Sample Output:
1 bar undefined
Flowchart:

Live Demo:
See the Pen javascript-basic-exercise-231-1 by w3resource (@w3resource) on CodePen.
Improve this sample solution and post your code through Disqus
Previous: Write a JavaScript program to get the human readable format of the given number of milliseconds.
Next: Write a JavaScript program that takes a function as an argument, then makes the first argument the last.
What is the difficulty level of this exercise?
Test your Programming skills with w3resource's quiz.
- Weekly Trends
- Python Interview Questions and Answers: Comprehensive Guide
- Scala Exercises, Practice, Solution
- Kotlin Exercises practice with solution
- MongoDB Exercises, Practice, Solution
- SQL Exercises, Practice, Solution - JOINS
- Java Basic Programming Exercises
- SQL Subqueries
- Adventureworks Database Exercises
- C# Sharp Basic Exercises
- SQL COUNT() with distinct
- JavaScript String Exercises
- JavaScript HTML Form Validation
- Java Collection Exercises
- SQL COUNT() function
- SQL Inner Join