This example is composed of two files:

• Source code(windowdialog.cpp)
• Resource script(script.rc)

//=============================================================================
//DIALOG: WINDOW - Copyright © 2000,2005 Ken Fitlike
//=============================================================================
//API functions used: CreateWindowEx,DefWindowProc,DispatchMessage,GetMessage,
//GetSystemMetrics,LoadImage,MessageBox,PostQuitMessage,RegisterClassEx,
//ShowWindow,UpdateWindow,TranslateMessage,WinMain.
//=============================================================================
//Demonstrates the creation of a window based on a unique window class
//derived from a dialog box.
//=============================================================================
#include <windows.h>  //include all the basics
#include <tchar.h>    //string and other mapping macros
#include <string>

//define an unicode string type alias
typedef std::basic_string<TCHAR> ustring;
//=============================================================================
//message processing function declarations
LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
void OnCommand(const HWND,int,int,const HWND);

//non-message function declarations
inline int ErrMsg(const ustring&);
//=============================================================================
int WINAPI WinMain(HINSTANCE hInst,HINSTANCE,LPSTR pStr,int nCmd)
{
ustring classname=_T("DLG_STRING_RESOURCE_NAME");
WNDCLASSEX wcx={0};  //used for storing information about the wnd 'class'

wcx.cbSize         = sizeof(WNDCLASSEX);           
wcx.lpfnWndProc    = WndProc;             //wnd Procedure pointer
wcx.cbWndExtra     = DLGWINDOWEXTRA;
wcx.hInstance      = hInst;               //app instance
//use 'LoadImage' to load wnd class icon and cursor as it supersedes the 
//obsolete functions 'LoadIcon' and 'LoadCursor', although these functions will 
//still work. Because the icon and cursor are loaded from system resources ie 
//they are shared, it is not necessary to free the image resources with either 
//'DestroyIcon' or 'DestroyCursor'.
wcx.hIcon         = reinterpret_cast<HICON>(LoadImage(0,IDI_APPLICATION,
                                            IMAGE_ICON,0,0,LR_SHARED));
wcx.hCursor       = reinterpret_cast<HCURSOR>(LoadImage(0,IDC_ARROW,
                                              IMAGE_CURSOR,0,0,LR_SHARED));
wcx.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_BTNFACE+1);   
wcx.lpszClassName = classname.c_str(); 
//the window 'class' (not c++ class) has to be registered with the system
//before windows of that 'class' can be created
if (!RegisterClassEx(&wcx))
  {
  ErrMsg(_T("Failed to register wnd class"));
  return -1;
  }

HWND hwnd=CreateDialog(hInst,classname.c_str(),0,0);

if (!hwnd)
  {
  ErrMsg(_T("Failed to create wnd"));
  return -1;
  }

ShowWindow(hwnd,nCmd); 
UpdateWindow(hwnd);
//start message loop - windows applications are 'event driven' waiting on user,
//application or system signals to determine what action, if any, to take. Note 
//that an error may cause GetMessage to return a negative value so, ideally,  
//this result should be tested for and appropriate action taken to deal with 
//it(the approach taken here is to simply quit the application).
MSG msg;
while (GetMessage(&msg,0,0,0)>0)
  {
  //make sure that default, system dialog box behaviour occurs
  if (!IsWindow(hwnd) || !IsDialogMessage(hwnd,&msg))
    {
    TranslateMessage(&msg);
    DispatchMessage(&msg);
    }
  }
return static_cast<int>(msg.wParam);
}
//=============================================================================
LRESULT CALLBACK WndProc(HWND hwnd,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
switch (uMsg)
  {
  case WM_COMMAND:
    {
    OnCommand(hwnd,LOWORD(wParam),HIWORD(wParam),
              reinterpret_cast<HWND>(lParam));
    return 0;
    }
  case WM_CREATE:
    {
    //Because it's a window based on a dialog resource but NOT a dialog 
    //box it receives a WM_CREATE message and NOT a WM_INITDIALOG message.
    return 0;
    }
  case WM_DESTROY:
    PostQuitMessage(0);    //signal end of application
    return 0;
  default:
    //let system deal with msg
    return DefDlgProc(hwnd,uMsg,wParam,lParam);  
  }
}
//=============================================================================
void OnCommand(const HWND hwnd,int id,int notifycode,const HWND hCntrl)
{
//handles WM_COMMAND message of the modal dialogbox
switch (id)
  {
  case IDOK:        //RETURN key pressed or 'ok' button selected
  case IDCANCEL:    //ESC key pressed or 'cancel' button selected
    DestroyWindow(hwnd);
  }
}
//=============================================================================
inline int ErrMsg(const ustring& s)
{
return MessageBox(0,s.c_str(),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
}
//=============================================================================

//=============================================================================
//WINDOW DIALOG - Copyright (c) 2000,2005 Ken Fitlike
//resource script
//
//Note that there is no resource define for the dialog - its identifier is a
//string which is the same as that used for the CLASS resource definition
//statement within the DIALOGEX resource definition statement.
//=============================================================================
#if !defined __BORLANDC__
#include <afxres.h>
#endif
//=============================================================================
//Resource languages: Codes for languages and sub-languages are declared in 
//winnt.h eg. for US english replace SUBLANG_ENGLISH_UK with SUBLANG_ENGLISH_US
//eg. for FRENCH replace LANG_ENGLISH with LANG_FRENCH and then replace 
//SUBLANG_ENGLISH_UK with either SUBLANG_FRENCH,SUBLANG_FRENCH_BELGIAN,
//SUBLANG_FRENCH_CANADIAN,SUBLANG_FRENCH_SWISS,SUBLANG_FRENCH_LUXEMBOURG,
//SUBLANG_FRENCH_MONACO depending on which national or regional variation of
//the language corresponds best with your requirements.
//
LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_UK  
//=============================================================================
//Dialog
//=============================================================================
DLG_STRING_RESOURCE_NAME DIALOGEX 0, 0, 252, 149
STYLE DS_CENTER | WS_MINIMIZEBOX | WS_MAXIMIZEBOX | WS_POPUP | WS_VISIBLE | 
      WS_CAPTION | WS_SYSMENU | WS_THICKFRAME
CAPTION "Dialog Box: Window"    
CLASS "DLG_STRING_RESOURCE_NAME"
FONT 8, "MS Sans Serif"
  {
  DEFPUSHBUTTON   "OK",IDOK,22,62,50,14
  PUSHBUTTON      "Cancel",IDCANCEL,111,63,50,14
  }
//=============================================================================