c++ create button

HWND hwndButton = CreateWindow( 
    L"BUTTON",  // Predefined class; Unicode assumed 
    L"OK",      // Button text 
    WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,  // Styles 
    10,         // x position 
    10,         // y position 
    100,        // Button width
    100,        // Button height
    m_hwnd,     // Parent window
    NULL,       // No menu.
    (HINSTANCE)GetWindowLongPtr(m_hwnd, GWLP_HINSTANCE), 
    NULL);      // Pointer not needed.