What is the Purpose of the CWinApp Class?

The CWinApp class in MFC is the base class for the application itself. It manages the application’s initialization, message handling, and termination.

When an MFC application starts, it creates an instance of a class derived from CWinApp. This instance controls the application’s overall behavior.

The key responsibilities of CWinApp include:

• Initializing the application and its resources.
• Creating the main window and message pump.
• Handling command-line arguments and application-level messages.
• Cleaning up resources before exiting.

Example:

class CMyApp : public CWinApp
{
public:
    virtual BOOL InitInstance();
};

BOOL CMyApp::InitInstance()
{
    CMyMainWindow* pFrame = new CMyMainWindow;
    m_pMainWnd = pFrame;
    pFrame->ShowWindow(SW_SHOW);
    return TRUE;
}

Here, InitInstance sets up the main window and shows it.