There are mainly 2 types of Win32 applications, console application and window application. They have different way in handling application exit. To force Window application to exit, you need to send out WM_CLOSE message to the main window handle. That's pretty simple to handle. You can hook up to Application.ApplicationExit or Form.Close at the form level. However, in a console application, it is a little bit different. Console applications are somehow modeled after DOS console application where usually an application exits when stdin is dead or Ctrl+C is pressed. To handle this properly in C#, you can set a delegate to SetConsoleCtrlHandler.You will have an opportunity to clean up resource or finish your work before the application actually exits.
// Declare the SetConsoleCtrlHandler function // as external and receiving a delegate. [DllImport("Kernel32")] public static extern bool SetConsoleCtrlHandler(HandlerRoutine Handler, bool Add); // A delegate type to be used as the handler routine // for SetConsoleCtrlHandler. public delegate bool HandlerRoutine(CtrlTypes CtrlType); // An enumerated type for the control messages // sent to the handler routine. public enum CtrlTypes { CTRL_C_EVENT = 0, CTRL_BREAK_EVENT, CTRL_CLOSE_EVENT, CTRL_LOGOFF_EVENT = 5, CTRL_SHUTDOWN_EVENT } private static bool ConsoleCtrlCheck(CtrlTypes ctrlType) { // Put your own handler here return true; } ... SetConsoleCtrlHandler(new HandlerRoutine(ConsoleCtrlCheck), true);