[Lazarus] Windows Registry, how do I read data from rdExpandString

[Bo Berglund]

I am writing a little Lazarus program to examine the registry values
stored by a program we use.
So far I have only used strings and integers in the registry, and I
have known in advance what type they are. Now I want to make a more
general kind of reader and so I have created a read function like
shown below.
So there is a case construct taht uses the data type reported on each
item, but I don't know what to do about rdExpandString.
In fact I don't know what kind of data may hide behind this data
type...

I would apprecieate to get some clarification on this because googling
has so far not resulted in anything for Pascal.

function ReadRegValues(Root: HKEY; Key: string; List: TStrings):
boolean;
var
  Reg: TRegistry;
  i: integer;
  sVal: string;
  siz: integer;
  DT: TRegDataType;
  BUF: TBytes;
begin
  List.Clear;
  Result := false;
  Reg := TRegistry.Create;
  try
    Reg.RootKey := Root;
    if not Reg.OpenKeyReadOnly(Key) then
      exit;
    try
      Reg.GetValueNames(List);
      for i := 0 to List.Count-1 do
      begin
        sVal := '';
        try
          if Reg.ValueExists(List[i]) then
          begin
            DT := Reg.GetDataType(List[i]);
  // one of (rdUnknown, rdString, rdExpandString, rdBinary, rdInteger)
            case DT of
              rdString:
                  sVal := Reg.ReadString(List[i]);
              rdExpandString: What to do here????;
              rdBinary:
                  begin
                    siz := Reg.GetDataSize(List[i]);
                    SetLength(BUF, siz);
                    sVal := '';
                    Reg.ReadBinaryData(List[i], BUF, siz);
                    for i := 0 to siz-1 do
                      sVal := sVal + IntToHex(BUF[i], 2) + ' ';
                  end;
              rdInteger:
                  sVal := IntToStr(Reg.ReadInteger(List[i]));
            end;

          end;
          List[i] := List[i] + '=' + sVal;
        except
        end;
      end;
      Result := true;
    except
    end;
  finally
    Reg.Free;
  end;
end;


-- 
Bo Berglund
Developer in Sweden