Notes

User.cspublic class User
{
public string Username { get; set; }
public string Password { get; set; }
}UserRepository.cspublic static class UserRepository
{
private static readonly List<User> _users = new List<User>
{
new User { Username = "user1", Password = "password1" },
new User { Username = "user2", Password = "password2" }
};

public static User GetUserByUsername(string username)
{
return _users.FirstOrDefault(u => u.Username.Equals(username, StringComparison.OrdinalIgnoreCase));
}
}AuthenticationService.cspublic class AuthenticationService
{
public bool Authenticate(string username, string password)
{
var user = UserRepository.GetUserByUsername(username);
return user != null && user.Password == password;
}
}AuthController.cs[ApiController]
[Route("api/[controller]")]
public class AuthController : ControllerBase
{
private readonly AuthenticationService _authenticationService;

public AuthController(AuthenticationService authenticationService)
{
_authenticationService = authenticationService;
}

[HttpPost("login")]
public IActionResult Login(LoginModel model)
{
if (_authenticationService.Authenticate(model.Username, model.Password))
{
return Ok(new { message = "Login successful" });
}
return Unauthorized();
}
}