if car_err<>MMSYSERR_NOERROR then
begin
Application.MessageBox(pchar('错误代码:'+vartostr (car_err)),'midi输出设备错误!');
exit;
end;
car_err:=midiStreamOut(hstream,@hTrack,sizeof(TMidiHdr));
if car_err<>MMSYSERR_NOERROR then
begin
Application.MessageBox(pchar('错误代码:'+vartostr(car_err)),'midi输出设备错误!');
exit;
end;