I just found a simple piece of code in my mail archive, i had sent in 2006.
//function performs the negation for integer.
public int getNegate(int n)
{
string strBin = ConvertToBin(n);
string strNegation = "";
int c,count,i;
int nDec;
if (strBin.Length != 8 )
for(i=strBin.Length; i<8; i++)
strBin = "0" + strBin;
count = 1;
while (count <= strBin.Length)
{
c = Convert.ToInt32(strBin.Substring(count-1,1));
if (c == 1)
strNegation = strNegation + "0";
else
strNegation = strNegation + "1";
count = count + 1;
}
nDec = ConvertDecimal(strNegation);
return nDec;
}


