10 进制转 2 进制、16 进制

function IntToBin(Value: LongInt; Size: Integer): String;
var
  i: Integer;
begin
  Result:='';
  for i:=Size-1 downto 0 do
  begin
    if Value and (1 shl i)<>0 then
      Result:=Result+'1'
    else
      Result:=Result+'0';
  end;
end;

//举例：
procedure TForm1.Button1Click(Sender: TObject);
var
  i: Integer;
  s: string;
begin
  for i := 0 to 255 do
  begin
    s := IntToStr(i) + #9;
    s := s + IntToHex(i,2) + #9;
    s := s + IntToBin(i,8);
    Memo1.Lines.Add(s);
  end;
end;