InputQuery ограниченное количество введенных символов

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop   //--- use  resurs.rc  winuser.h
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
  HINSTANCE h;
  HWND hw;
  char buf[256];
  const int maxlenth = 6;
//---------------------------------------------------------------------------
BOOL CALLBACK DlgProc(HWND hw, UINT msg, WPARAM wp, LPARAM lp)
{ 
  switch (msg) {
    case WM_INITDIALOG:
      SendDlgItemMessage(hw,3000,EM_SETLIMITTEXT,(WPARAM)maxlenth,-1L);
      return TRUE;
    case WM_COMMAND:
      if (LOWORD(wp)==3002) GetDlgItemText(hw,3000,buf,256);
      if (LOWORD(wp)==3001 || LOWORD(wp)==3002) EndDialog(hw,0); 
  }
  return FALSE;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
   for(int i=0;i<256;i++) buf[i]=0;
   DialogBox(h,"ID_A",hw,(DLGPROC)DlgProc);
   Edit1->Text = buf;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
     Close();
}
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
ID_A DIALOG 10, 10, 100, 47
STYLE DS_MODALFRAME | DS_3DLOOK | DS_CENTER | WS_VISIBLE | WS_CAPTION
CAPTION "My Dialog Box"
{
 EDITTEXT 3000, 8, 6, 86, 13, ES_AUTOHSCROLL
 DEFPUSHBUTTON "Cancel", 3001, 12, 27, 35, 13
 PUSHBUTTON "OK", 3002, 54, 27, 35, 13
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{      //   AnsiString otzyv ;
    TButton *bu2;
    TMsgDlgButtons Buttons = TMsgDlgButtons() << mbYes << mbNo;
    TForm *aMsgDlg = CreateMessageDialog("", mtCustom, Buttons);
    TEdit *died1 = new TEdit(aMsgDlg); died1->Parent = aMsgDlg;
    died1->MaxLength = 6;
    aMsgDlg->Caption = "Ввод теекста";
    aMsgDlg->ClientWidth = 210;
    int p=-1; while(++p<aMsgDlg->ControlCount)  {
      bu2=dynamic_cast<TButton*>(aMsgDlg->Controls[p]);
      if(bu2 && bu2->Name=="Yes") { bu2->Caption = "Отмена";
         bu2->SetBounds(15,42,57,25); }
      if(bu2 && bu2->Name=="No" ) { bu2->Caption = "Ввод";
         bu2->SetBounds(138,42,57,25); }   }
    died1->SetBounds(15,10,180,21);
    if(7==aMsgDlg->ShowModal()) otzyv = died1->Text;
    delete  aMsgDlg;
    Edit1->Text = otzyv;
}