Checking if a string contains substring in JavaScript

In this tutorial, we are going to learn about how to check if a string contains another substring or not in JavaScript

Using includes method

To check if a string contains substring, we can use the built-in includes() method in JavaScript.

let string = "how are you";
let substring = "you";

console.log(string.includes(substring)); // true

The includes() method returns true if a substring is found; else it returns false.

Similarly, we can also use the indexOf() method, where it returns -1 if a string doesn’t contain a substring; else it returns the index of the substring.

Example:

let string = "how are you";
let substring = "you";

console.log(string.indexOf(substring) !== -1); // true

console.log(string.indexOf('fun') !== -1); // false