Delegates vs Events, Kyiv 2010

delegate.cs

public class UserManager {
  //This class allows other code to perform username/password validation.  Which is the better way to do this?

  public class AuthenticateUserEventArgs : EventArgs {
    public string UserName { get; set; }
    public string Password { get; set; }
  }

  // This is one way
  public event EventHandler<AuthenticateUserEventArgs> AuthenticateUser;

  // This is another way
  public Func<string, string, bool> AuthenticatedUser { get; set; }
}

event.cs

public class UserManager {
  // This class notifies other code when a user logs on.  Which is the better way to do this?

  // This is one way
  public event EventHandler UserLoggedOn;

  // This is another way
  public Action UserLoggedOn { get; set; }
}