Twos Complement Binary Converter

1000
11111111111111111111111111110111
11111111111111111111111111111000

 public static string DecToBinTwo(int dec)

        {

            int bit;

            string result = "";
            string flipped = "";
            string final = "";
            int count = 0;
            int itercount = 0;


            dec = Math.Abs(dec);


            while (dec > 0)

            {

                itercount++;

                bit = dec % 2;

                result = bit.ToString() + result;

                dec = dec / 2;

            }

            for (int i = result.Length-1; i >= 0; i--)
            {
                if (result[i] == '0')
                {
                    flipped += '1';
                }
                else
                {
                    flipped += '0';
                }
            }


            for (int i = flipped.Length-1; i >= 1; i--)
            {
                if ((flipped[i] == '0') && (count == 0))
                {
                    count++;

                    final += "1";
                }
                else

                {
                    final += flipped[i];

                }
            }

            return final;
        }

int dec = 8;
int notDec  = ~dec;
int plusOne = notDec + 1;

Console.WriteLine(Convert.ToString(dec, 2));
Console.WriteLine(Convert.ToString(notDec, 2));
Console.WriteLine(Convert.ToString(plusOne, 2));