Exercise 17: Check if String is Valid Email

Problem Statement

Create a function `isValidEmail(email)` that validates email using regex. Example: - isValidEmail("test@example.com") → true - isValidEmail("invalid") → false

Sample Output:

isValidEmail("test@example.com") => true
isValidEmail("invalid") => false
isValidEmail("user@domain.co.in") => true

Solution

const isValidEmail = (email) => {
  const regex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
  return typeof email === "string" && regex.test(email);
};

Explanation

Overall Goal:

  • Email format validate karna using regex.
  • Basic format check: local@domain.extension.

Line 1: Function header

  • const isValidEmail = (email) => {

Line 2: Regex pattern

  • const regex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
  • ^ → start of string.
  • [^\s@]+ → one or more non-whitespace, non-@ characters.
  • @ → literal @ symbol.
  • [^\s@]+ → domain part.
  • \. → literal dot.
  • [^\s@]+ → extension.
  • $ → end of string.

Line 3: Test

  • return typeof email === "string" && regex.test(email);
  • String hai aur regex match karta hai.

Real world:

  • Form validation: email input fields.
  • User registration: email verification.
  • Contact forms: email validation.