Convert octal to binary

Use OctToBin function to convert number in octal format to binary format.

function OctToBin(OctStr: string): string;

  function DecToBinStr(N: Integer): string;
  var
    S: string;
    i: Integer;
  begin
    if N<>0 then
      for i:=1 to SizeOf(N)*8 do
      begin
        if N1) do
        Delete(Result, 1, 1);
  end;
end;