If you are a developer working with JavaScript, you might have come across situations where you need to check if an object is empty.

An empty object is one that doesn’t have any properties or values. In JavaScript, there are several ways to check if an object is empty. In this article, we will discuss and understand some of the best ways to check if an object is empty in JavaScript.

What is an Empty Object in JavaScript

Before we dive into the ways to check if an object is empty, let’s first understand what is an empty object in JavaScript. In JavaScript, an object is considered empty only if it doesn’t have any properties or values in it . An empty object can be represented in the following ways as shown below .

const emptyObject = {}; // an object with no properties
const objectWithEmptyValues = { prop1: undefined, prop2: null }; // an object with empty values

Now we are going to understand the top 10 ways to check if an object is empty in javascript . 8th one is my favourite .

Using Object.keys()

One of the easiest ways to check if an object is empty is by using the Object.keys() method. This method returns an array of a given object’s property names. If the length of the array is 0, then the object is empty. Here’s an example .

const obj = {};
if (Object.keys(obj).length === 0) {
  console.log("Object is empty");
}

I generally use this in my backend code a lot .

Using for…in Loop

Another way to check if an object is empty is by using a for…in loop. This loop iterates over all enumerable properties of an object. If the loop doesn’t find any properties, then the object is empty. Here’s an example .

const obj = {};
let isEmpty = true;
for (let prop in obj) {
  isEmpty = false;
  break;
}
if (isEmpty) {
  console.log("Object is empty");
}

Using JSON.stringify()

You can also check if an object is empty by using JSON.stringify() method. This method converts a JavaScript object into a JSON string. If the object is empty, then the resulting string will be “{}”. Here’s how you can check .

const obj = {};
if (JSON.stringify(obj) === "{}") {
  console.log("Object is empty");
}

Note :- We can use this technique mostly in REST API and Frontend .

Using Object.getOwnPropertyNames()

Object.getOwnPropertyNames() method returns an array of all properties (including non-enumerable properties) found directly in a given object. If the length of the array is 0, then the object is empty. Here’s an example .

const obj = {};
if (Object.getOwnPropertyNames(obj).length === 0) {
  console.log("Object is empty");
}

Using Object.entries()

Another way to check if an object is empty is by using Object.entries() method. This method returns an array of an object’s own enumerable property [key, value] pairs. If the length of the array is 0, then the object is empty. Here’s an example

const obj = {};
if (Object.entries(obj).length === 0) {
  console.log("Object is empty");
}

Using lodash.isEmpty()

If you are using the Lodash library in your JavaScript project, you can use the lodash.isEmpty() method to check if an object is empty. This method checks if the given value is an empty object, collection, map, or set. Here’s an example below .

const obj = {};
if (_.isEmpty(obj)) {
  console.log("Object is empty");
}

Using the length Property

If an object has a length property, you can check if it is empty by using this property. However, this method is not reliable because not all objects have a length property. Here’s how .

const arr = [];
if (arr.length === 0) {
  console.log("Array is empty");
}

Using the not Operator

You can also check if an object is not empty by using the not (!) operator. This operator returns the boolean opposite of a given value. If the object is empty, then it will return true. Here’s an example .

const obj = {};
if (!obj) {
  console.log("Object is empty");
}

Using the typeof Operator

You can also use the typeof operator to check if an object is empty. If the object is empty, the typeof operator will return “object”. Here’s an example .

const obj = {};

if (typeof obj === "object" && Object.keys(obj).length === 0) {
  console.log("Object is empty");
}

Using the hasOwnProperty() Method

The hasOwnProperty() method checks if a property is a direct property of an object or not. If an object doesn’t have any properties, then it is empty. Here’s an example:

const obj = {};

if (!obj.hasOwnProperty()) {
  console.log("Object is empty");
}

Using the Object.values() Method

The Object.values() method returns an array of a given object’s own enumerable property values. If the length of the array is 0, then the object is empty. Here’s an example:

const obj = {};

if (Object.values(obj).length === 0) {
  console.log("Object is empty");
}

Conclusion

In this article, we have discussed some of the best ways to check if an object is empty in JavaScript. Whether you use the Object.keys(), for…in loop, JSON.stringify(), or any other method, the important thing is to choose the one that works best for your specific use case. By implementing these methods, you can ensure that your code is more efficient and accurate.