Bin -> Dec

function BinToInt(const Value: string): Integer;

var
  i, strLen: Integer;
begin
  Result := 0;
  strLen := Length(Value);
  for i := 1 to strLen do
    if Value[i] = '1' then
      Result := Result or (1 shl (strLen - i))
    else
      Result := Result and not (1 shl (strLen - i));
end;