How to Check If Array Is Empty or Does Not Exist?

When working with JavaScript, it is common to come across situations where you need to check if an array is empty or does not exist. In this blog post, we will explore different solutions to tackle this problem.

Solution 1: Using the length property

One way to check if an array is empty is by using the length property. The length property returns the number of elements in an array. If the length is 0, it means the array is empty.

const myArray = [];

if (myArray.length === 0) {
  console.log("Array is empty");
} else {
  console.log("Array is not empty");
}

Solution 2: Using the Array.isArray() method

Another way to check if an array exists is by using the Array.isArray() method. This method returns true if the provided value is an array, and false otherwise.

const myArray = [];

if (Array.isArray(myArray) && myArray.length === 0) {
  console.log("Array is empty");
} else {
  console.log("Array is not empty");
}

Solution 3: Using the typeof operator

The typeof operator returns the type of a variable. If the array does not exist, it will return "undefined". We can use this information to check if the array exists or not.

const myArray = undefined;

if (typeof myArray === "undefined" || myArray.length === 0) {
  console.log("Array is empty or does not exist");
} else {
  console.log("Array is not empty");
}

These are three different ways to check if an array is empty or does not exist in JavaScript. Choose the solution that best fits your needs and implement it in your code.

Remember, it is always a good practice to handle edge cases like empty or non-existent arrays to ensure your code behaves as expected.