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* 소스
const SHFMT_DRV_A = 0;
const SHFMT_DRV_B = 1;

const SHFMT_ID_DEFAULT = $FFFF;

const SHFMT_OPT_QUICKFORMAT = 0;
const SHFMT_OPT_FULLFORMAT = 1;
const SHFMT_OPT_SYSONLY = 2;

const SHFMT_ERROR = -1;
const SHFMT_CANCEL = -2;
const SHFMT_NOFORMAT = -3;

function SHFormatDrive(hWnd : HWND;
                       Drive : Word;
                       fmtID : Word;
                       Options : Word) : Longint
   stdcall; external 'Shell32.dll' name 'SHFormatDrive';

procedure TForm1.Button1Click(Sender: TObject);
var
  FmtRes : longint;
begin
  try
    FmtRes:= ShFormatDrive(Handle,
                           SHFMT_DRV_A,
                           SHFMT_ID_DEFAULT,
                           SHFMT_OPT_QUICKFORMAT);
    case FmtRes  of
     SHFMT_ERROR : ShowMessage('Error formatting the drive');
     SHFMT_CANCEL :
       ShowMessage('User canceled formatting the drive');
     SHFMT_NOFORMAT : ShowMessage('No Format')
    else
     ShowMessage('Disk has been formatted');
    end;
  except
  end;

end