Question
What is the best way to delete the last element from a JavaScript array?
const array = [1, 2, 3, 4, 5];
array.pop(); // Removes the last element (5)
console.log(array); // Output: [1, 2, 3, 4]
Answer
In JavaScript, the most common and efficient way to remove the last element from an array is by using the `pop()` method. This method not only removes the last element but also returns that element, allowing you to store it if needed.
const array = [1, 2, 3, 4, 5];
const lastElement = array.pop(); // lastElement will be 5
console.log(array); // Output: [1, 2, 3, 4]
// Using slice to keep the original array intact:
const newArray = array.slice(0, -1);
console.log(newArray); // Output: [1, 2, 3, 4]
Solutions
- Use the `pop()` method, which removes the last element and modifies the original array.
- If you need to keep the original array intact, use the `slice()` method to create a new array without the last element.
Common Mistakes
Mistake: Using `delete array[array.length - 1];`
Solution: Using `delete` only removes the last element but leaves a hole in the array. Instead, use `array.pop()`.
Mistake: Not handling the case when the array is empty before using `pop()`
Solution: Check if the array length is greater than 0 to avoid errors when calling `pop()`.
Helpers
- JavaScript array remove last element
- delete last element array JavaScript
- JavaScript pop method
- JavaScript array methods
