Delphi Stream to String

function StreamToString(aStream: TStream): string;
var
  SS: TStringStream;
begin
  if aStream <> nil then
  begin
    SS := TStringStream.Create('');
    try
      SS.CopyFrom(aStream, 0); 
      Result := SS.DataString;
    finally
      SS.Free;
    end;
  end else
  begin
    Result := '';
  end;
end;