Код выполнения окна

String FileName;
// ...
if (OpenDialog1->Execute() ) // вызывать окно и если пользователь выбирет файл
{
  FileName = OpenDialog1->FileName;
  DoSomethingWithThisFile(FileName);
}

CoInitializeEx(NULL, COINIT_APARTMENTTHREADED|COINIT_DISABLE_OLE1DDE);
SHELLEXECUTEINFO sei = { sizeof(sei) };
sei.fMask = SEE_MASK_NOASYNC;
sei.nShow = SW_SHOWNORMAL;
sei.lpVerb = _T("openas");
sei.lpFile = _T("D:\\test.ext");
ShellExecuteEx(&sei);

#define SEE_MASK_NOASYNC 0x00000100
 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
    CoInitializeEx(NULL, COINIT_APARTMENTTHREADED|COINIT_DISABLE_OLE1DDE);
    SHELLEXECUTEINFO sei = { sizeof(sei) };
    sei.fMask = SEE_MASK_NOASYNC;
    sei.nShow = SW_SHOWNORMAL;
    sei.lpVerb = "openas";
    sei.lpFile = ""D:\\test.ext"";
    ShellExecuteEx(&sei);
}

//---------------------------------------------------------------------------
 
#include <vcl.h>
#include <utilcls.h>
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
#define SEE_MASK_NOASYNC 0x00000100
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
  CoInitializeEx(NULL, COINIT_APARTMENTTHREADED|COINIT_DISABLE_OLE1DDE);
  SHELLEXECUTEINFO sei = { sizeof(sei) };
  sei.fMask = SEE_MASK_NOASYNC;
  sei.nShow = SW_SHOWNORMAL;
  sei.lpVerb = _T("openas");
  sei.lpFile = _T("D:\\test.ext");
  ShellExecuteEx(&sei);
}
//---------------------------------------------------------------------------