js check if string contains value code example

Example 1: string contains in javascript

const string = "foo";
const substring = "oo";

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

Example 2: how to identify specific letter from a string in javascript

var str = "Hello world, welcome to the universe.";
var n = str.includes("world", 12);

Example 3: js check if string contains character

"FooBar".includes("oo"); // true

"FooBar".includes("foo"); // false

"FooBar".includes("oo", 2); // false