if (isset($_POST['email'])) { $email = $_POST['email']; if (!filter_var($email, FILTER_VALIDATE_EMAIL)) { echo "Invalid email format"; } }
if (isset($_POST['password'])) { $password = $_POST['password']; if (strlen($password) < 7) { echo "Password must be at least 7 characters long"; } }The package library that is commonly used with PHP Post validate is the Filter extension, which provides a large set of useful filtering functions. It is a built-in library that doesn't require any additional installation.