Win32 SDK (dialog box Program)

#include <Windows.h>
#include <tchar.h>
#include "resource.h"

TCHAR DlgName[]=TEXT("MyDialog");
TCHAR AppName[]=TEXT("Dialog");;
//TCHAR TestString[]=TEXT("hello world");

TCHAR buffer1[512];
TCHAR buffer2[512];
TCHAR *buffer3=NULL;
int a=0,b=0,c=0;
HINSTANCE g_hInstance;

INT_PTR CALLBACK WinProc(HWND hWnd,UINT Msg,WPARAM wParam,LPARAM lParam);

int WINAPI WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd )
{
    g_hInstance=hInstance;
    DialogBoxParam(hInstance,DlgName,NULL,(DLGPROC)WinProc,NULL);
return 0;
}

INT_PTR CALLBACK WinProc(HWND hWnd,UINT Msg,WPARAM wParam,LPARAM lParam)
{
switch(Msg)
    {
case WM_INITDIALOG:
        SetFocus(GetDlgItem(hWnd,IDC_EDIT1));
break;
case WM_COMMAND:
if (lParam==0)
        {
switch(wParam)
            {
case ID_TESTCONTROL_GETTEXT:
                GetDlgItemText(hWnd,IDC_EDIT1,buffer3,512);
                MessageBox(hWnd,buffer3,AppName,MB_OK);
break;
case ID_TESTCONTROL_CLEARTEXT:
                SetDlgItemText(hWnd,IDC_EDIT1,NULL);
                SetDlgItemText(hWnd,IDC_EDIT2,NULL);
                SetDlgItemText(hWnd,IDC_EDIT3,NULL);
break;
case ID_TESTCONTROL_EXIT:
                EndDialog(hWnd,NULL);
break;
            }
        }
else
        {
if (HIWORD(wParam)==BN_CLICKED)
            {
switch(LOWORD(wParam))
                {
case IDOK:
                    GetDlgItemText(hWnd,IDC_EDIT1,buffer1,512);
                    GetDlgItemText(hWnd,IDC_EDIT2,buffer2,512);
                    a=_ttoi(buffer1);
                    b=_ttoi(buffer2);
                    c=a+b;
//    buffer3=;
                    SetDlgItemText(hWnd,IDC_EDIT3,buffer3);
break;
case IDCANCEL:
                    EndDialog(hWnd,NULL);
break;
                }

            }
        }
break;
default:
return FALSE;
    }
return TRUE;


}

* **. RC:

Mydialog dialogex 0, 0,419,204
Style ds_setfont | ds_modalframe | ds_3dlook | ds_fixedsys | ds_center | ws_minimizebox | ws_visible | ws_caption | ws_sysmenu
Caption "dialog"
Menu idr_menu2
Font 8, "Ms shell DLG", 400, 0, 0x1
Begin
Defpushbutton "OK", idok, 181,10, 50,14
Pushbutton "cancel", idcancel
Edittext idc_edit1, 27,9, 50,17, es_autohscroll
Edittext idc_edit2, 101,8, 52,18, es_autohscroll
Edittext idc_edit3, 63,35, 51,17, es_autohscroll
Control "", idc_static, "static", ss_blackframe, 175,110
End


//////////////////////////////////////// /////////////////////////////////////
//
// Menu
//

Idr_menu2 menu
Begin
Popup "Test Control"
Begin
Menuitem "get text", id_testcontrol_gettext
Menuitem "clear text", id_testcontrol_cleartext
Menuitem "exit", id_testcontrol_exit
End
End

* **. H:

#define IDD_DIALOG1                     101
#define IDR_MENU1                       102
#define IDR_MENU2                       103
#define IDC_EDIT1                       1001
#define IDC_EDIT2                       1002
#define IDC_EDIT3                       1003
#define ID_TESTCONTROL_GETTEXT          40001
#define ID_TESTCONTROL_CLEARTEXT        40002
#define ID_TESTCONTROL_EXIT             40003

// Next default values for new objects
// 
#ifdef APSTUDIO_INVOKED
#ifndef APSTUDIO_READONLY_SYMBOLS
#define _APS_NEXT_RESOURCE_VALUE        104
#define _APS_NEXT_COMMAND_VALUE         40004
#define _APS_NEXT_CONTROL_VALUE         1004
#define _APS_NEXT_SYMED_VALUE           101
#endif
#endif