JavaScript arrays are mutable, meaning that their contents can be changed. One way to change the contents of an array is to sort it. The sort() method allows you to sort the elements of an array in ascending or descending order.
Sorting Arrays of Numbers
To sort an array of numbers in ascending order, you can use the following code:
const numbers = [5, 10, 3, 2, 1];
numbers.sort();
console.log(numbers);
This will output the following to the console:
[1, 2, 3, 5, 10]
To sort an array of numbers in descending order, you can use the following code:
const numbers = [5, 10, 3, 2, 1];
numbers.sort((a, b) => b - a);
console.log(numbers);
This will output the following to the console:
[10, 5, 3, 2, 1]
Sorting Arrays of Strings
To sort an array of strings in ascending order, you can use the following code:
const strings = ["apple", "banana", "orange", "cherry"];
strings.sort();
console.log(strings);
This will output the following to the console:
["apple", "banana", "cherry", "orange"]
To sort an array of strings in descending order, you can use the following code:
const strings = ["apple", "banana", "orange", "cherry"];
strings.sort((a, b) => b.localeCompare(a));
console.log(strings);
This will output the following to the console:
["orange", "cherry", "banana", "apple"]
Sorting Arrays of Objects
To sort an array of objects, you can use the sort() method and provide a compare function. The compare function should compare two elements of the array and return a negative number if the first element should come before the second element, a positive number if the second element should come before the first element, and 0 if the elements should remain in the same order.
For example, the following code sorts an array of objects by their name property in ascending order:
const objects = [{ name: "Alice" }, { name: "Bob" }, { name: "Carol" }];
objects.sort((a, b) => a.name.localeCompare(b.name));
console.log(objects);
This will output the following to the console:
[
{ name: "Alice" },
{ name: "Bob" },
{ name: "Carol" }
]
You can also use the sort() method to sort an array of objects by a nested property. For example, the following code sorts an array of objects by their age property in descending order:
const objects = [
{ name: "Alice", age: 25 },
{ name: "Bob", age: 30 },
{ name: "Carol", age: 20 }
];
objects.sort((a, b) => b.age - a.age);
console.log(objects);
This will output the following to the console:
[
{ name: "Bob", age: 30 },
{ name: "Alice", age: 25 },
{ name: "Carol", age: 20 }
]
Conclusion
The sort() method is a powerful tool for sorting arrays in JavaScript. You can use it to sort arrays of numbers, strings, objects, and any other type of data. By providing a compare function, you can customize the sorting algorithm to meet your specific needs.