JavaScript String Search

JavaScript provides several methods for searching within strings to find specific substrings or characters. These methods include indexOf(), lastIndexOf(), search(), and match().

1. indexOf()

Returns the index of the first occurrence of a specified substring within the string.

const str = "Hello, world!";
console.log(str.indexOf("world")); // Output: 7

2. lastIndexOf()

Returns the index of the last occurrence of a specified substring within the string.

const str = "Hello, world, world!";
console.log(str.lastIndexOf("world")); // Output: 13

3. search()

Searches for a specified substring within the string and returns the index of the first match.

const str = "Hello, world!";
console.log(str.search("world")); // Output: 7

4. match()

Searches the string for a specified pattern and returns an array of matches.

const str = "The rain in Spain falls mainly in the plain.";
const regex = /ain/g;
console.log(str.match(regex)); // Output: ["ain", "ain", "ain", "ain"]

These are some of the string search methods available in JavaScript. Each method has its specific use case and can be utilized to find substrings or patterns within strings efficiently.