JavaScript Arrays - Sorting and Reversing

Arrays in JavaScript often need to be organized or reversed based on the specific requirements of an application. In this guide, we'll explore how to sort and reverse array elements using JavaScript and provide sample code to illustrate these techniques.

Sorting an Array

JavaScript provides the sort() method to sort the elements of an array. By default, it sorts elements as strings, resulting in lexicographical (alphabetical) order:

const fruits = ['apple', 'banana', 'cherry', 'date', 'fig'];
// Sort the array in alphabetical order
fruits.sort();
console.log(fruits); // Outputs: ['apple', 'banana', 'cherry', 'date', 'fig']
    

If you need to sort an array of numbers, you can provide a sorting function as an argument to sort():

const numbers = [100, 30, 50, 10, 200];
// Sort the array in ascending numerical order
numbers.sort((a, b) => a - b);
console.log(numbers); // Outputs: [10, 30, 50, 100, 200]
    

Reversing an Array

To reverse the order of elements in an array, you can use the reverse() method:

const colors = ['red', 'green', 'blue', 'yellow'];
// Reverse the array
colors.reverse();
console.log(colors); // Outputs: ['yellow', 'blue', 'green', 'red']
    

Custom Sorting

If you need to perform custom sorting, you can use the sort() method with a custom comparison function:

const books = [
    { title: 'Harry Potter', pages: 400 },
    { title: 'Lord of the Rings', pages: 1200 },
    { title: 'The Hobbit', pages: 300 },
];
// Sort the array by the number of pages
books.sort((a, b) => a.pages - b.pages);
console.log(books);
// Outputs: [
//   { title: 'The Hobbit', pages: 300 },
//   { title: 'Harry Potter', pages: 400 },
//   { title: 'Lord of the Rings', pages: 1200 }
// ]
    

Conclusion

Sorting and reversing arrays are common operations in JavaScript when dealing with data. JavaScript's array methods make it easy to organize and manipulate the order of array elements, whether they are strings, numbers, or custom objects.

Experiment with sorting and reversing arrays in your JavaScript projects to efficiently manage and display data in the desired order.