Setting Default Printer di Delphi

procedure SetDefaultPrinter(PrinterName: String) ;
var
___j: Integer;
___Device : PChar;
___Driver : Pchar;
___Port : Pchar;
___HdeviceMode: Thandle;
___aPrinter : TPrinter;
begin
___Printer.PrinterIndex := -1;
___getmem(Device, 255) ;
___getmem(Driver, 255) ;
___getmem(Port, 255) ;
___aPrinter := TPrinter.create;
___for j := 0 to Printer.printers.Count-1 do
___begin
______if Printer.printers[j] = PrinterName then
______begin___
_________aprinter.printerindex := i;
_________aPrinter.getprinter(device, driver, port, HdeviceMode) ;
_________StrCat(Device, ',') ;___
_________StrCat(Device, Driver ) ;
_________StrCat(Device, Port ) ;
_________WriteProfileString('windows', 'device', Device) ;
_________StrCopy( Device, 'windows' ) ;
_________SendMessage(HWND_BROADCAST, WM_WININICHANGE,0, Longint(@Device)) ;
______end;
___end;
___Freemem(Device, 255) ;
___Freemem(Driver, 255) ;
___Freemem(Port, 255) ;___
___aPrinter.Free;
end;