Dicas Delphi - Acertando a Data e Hora do Sistema

procedure TForm1.Button1Click(Sender: TObject);
var
DataHora: TSystemTime;
Data, Hora: TDateTime;
Ano, Mes, Dia,
H, M, S, Mil: word;
begin
Data := StrToDate(Edit1.Text);
Hora := StrToTime(Edit2.Text);
DecodeDate(Data, Ano, Mes, Dia);
DecodeTime(Hora, H, M, S, Mil);
with DataHora do
begin
wYear := Ano;
wMonth := Mes;
wDay := Dia;
wHour := H;
wMinute := M;
wSecond := S;
wMilliseconds := Mil;
end;
SetLocalTime(DataHora);
end;

No Edit1 digite a nova data e no Edit2 digite a nova hora.