双对象列表，双字符串列表[2]

end;

function tdoublestring.data2getdata1(astring: string): string;
begin
  result := strings1.strings[indexofdata2(astring)];
end;

destructor tdoublestring.destroy;
begin
  strings1.free;
  strings2.free;
  inherited;
end;

function tdoublestring.indexofdata1(aindex: integer): string;
begin
  result := strings1.strings[aindex];
end;

function tdoublestring.indexofdata1(astring: string): integer;
begin
  result := strings1.indexof(astring);
end;

function tdoublestring.indexofdata2(astring: string): integer;
begin
  result := strings2.indexof(astring);
end;

function tdoublestring.indexofdata2(aindex: integer): string;
begin
  result := strings2.strings[aindex];