Efficiently Remove the Last Element from an Array in JavaScript [6 Methods Explained]

Efficiently Remove the Last Element from an Array in JavaScript

To remove the last element from an array in Javascript:

1. Create an array that contains some items - let numbers = [1, 2, 3, 4, 5].
2. Use numbers.pop() method to remove the last element from the array.

We will describe multiple methods in this post in order to do that. From using the pop, splice, and slice methods to utilizing the length property and the shift method, we will cover all the techniques you need to know to effectively remove the last element from an array in JavaScript. So, let's get started and learn how to master array manipulation in JavaScript!

Using the .pop() method:

The .pop() method is a simple and straightforward way to remove the last element from an array in JavaScript. It removes the last element from an array and returns the element that was removed. This method is particularly useful when you need to keep track of the element that was removed.

let numbers = [1, 2, 3, 4, 5];

numbers.pop();

console.log(numbers); // Output: [1, 2, 3, 4]

Using the .splice() method:

The .splice() method is another way to remove the last element from an array in JavaScript. This method allows you to add or remove elements from an array at a specified index. To remove the last element, you can pass in -1 as the first argument, and 1 as the second argument.

let numbers = [1, 2, 3, 4, 5];

numbers.splice(-1,1);

console.log(numbers); // Output: [1, 2, 3, 4]

Using the .slice() method:

The .slice() method is used to create a new array by extracting elements from an existing array. To remove the last element, you can pass in 0 as the first argument and -1 as the second argument. This will extract all elements except the last one, creating a new array without the last element.

let numbers = [1, 2, 3, 4, 5];

let newArray = numbers.slice(0,-1);

console.log(newArray); // Output: [1, 2, 3, 4]

Using the .length property:

The .length property can be used to remove the last element from an array in JavaScript. By reducing the length of the array by one, the last element will be removed. However, it's not recommended to use this method as it can cause performance issues on large arrays.

let numbers = [1, 2, 3, 4, 5];

numbers.length = numbers.length -1;

console.log(numbers); // Output: [1, 2, 3, 4]

Using the .shift() method:

The .shift() method removes the first element of an array and returns the removed element. To remove the last element, you can use this method in combination with reverse the array and then use the shift method to remove the first element.

let numbers = [1, 2, 3, 4, 5];

numbers.shift();

console.log(numbers); // Output: [2, 3, 4, 5]

Using the .slice() method in combination with the spread operator:

The spread operator(...) can be used to create a new array that does not mutate the original array. Using the .slice() method in combination with the spread operator to create a new array that contains all elements except the last one

let numbers = [1, 2, 3, 4, 5];

let newArray = [...numbers.slice(0, -1)];

console.log(newArray); // Output: [1, 2, 3, 4]

It's worth noting that using .pop(), .splice() and .slice() will mutate the original array, while using .length and .shift() will also mutate the original array but .length is not recommended because it may cause performance issues on large arrays. Using the spread operator in combination with .slice() will create a new array and it will not mutate the original array.