var
Device:array[0..cchDeviceName-1]of char;
Driver:array[0..MAX_PATH-1] of char;
port:array[0..32] of char;
hDMode:THandle;
begin
printer.GetPrinter(Device,Driver,port,hDMode);
if printer.PrinterIndex=0 then Messagedlg('你需要安装打印机才能打印!',mtError,[mbOk],0);
end;