Delphi从UTC (GMT)返回时差

Delphi/Pascal view sourceprint?1 function TimeZoneBias: Integer; 

 var

   TZI: Windows.TTimeZoneInformation; // info about time zone 

 begin

   if Windows.GetTimeZoneInformation(TZI) = Windows.TIME_ZONE_ID_INVALID then

     SysUtils.RaiseLastOSError; 

   Result := TZI.Bias 

 end;