Disable closing button on opened modal dialogs Windows Forms C#

Question

Say I open a dialog like this:

        Login login = new Login();
        if(login.ShowDialog(this) != DialogResult.OK)
            Application.Exit();

Now, login form has a close button in the menu by standard, and closing it seem to either return DialogResult.OK or no dialogresult at all and my application continues without repercussions. How to solve that problem?

Answer 1

Set the ControlBox property to false.