how to use XOR in c#

class XOR
{
    static void Main()
    {
        // Logical exclusive-OR

        // When one operand is true and the other is false, exclusive-OR
        // returns True.
        Console.WriteLine(true ^ false);
        // When both operands are false, exclusive-OR returns False.
        Console.WriteLine(false ^ false);
        // When both operands are true, exclusive-OR returns False.
        Console.WriteLine(true ^ true);


        // Bitwise exclusive-OR

        // Bitwise exclusive-OR of 0 and 1 returns 1.
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0x0 ^ 0x1, 2));
        // Bitwise exclusive-OR of 0 and 0 returns 0.
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0x0 ^ 0x0, 2));
        // Bitwise exclusive-OR of 1 and 1 returns 0.
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0x1 ^ 0x1, 2));

        // With more than one digit, perform the exclusive-OR column by column.
        //    10
        //    11
        //    --
        //    01
        // Bitwise exclusive-OR of 10 (2) and 11 (3) returns 01 (1).
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0x2 ^ 0x3, 2));

        // Bitwise exclusive-OR of 101 (5) and 011 (3) returns 110 (6).
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0x5 ^ 0x3, 2));

        // Bitwise exclusive-OR of 1111 (decimal 15, hexadecimal F) and 0101 (5)
        // returns 1010 (decimal 10, hexadecimal A).
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0xf ^ 0x5, 2));

        // Finally, bitwise exclusive-OR of 11111000 (decimal 248, hexadecimal F8)
        // and 00111111 (decimal 63, hexadecimal 3F) returns 11000111, which is
        // 199 in decimal, C7 in hexadecimal.
        Console.WriteLine("Bitwise result: {0}", Convert.ToString(0xf8 ^ 0x3f, 2));
    }
}

int d1 = Convert.ToInt32(hex1, 16);
int d2 = Convert.ToInt32(hex2, 16);
int r = dec1 ^ dec2;

a = a ^ c;   (or simply:   a ^= c;)

static private byte CalCheckSum(byte[] _PacketData,int PacketLength)
       {
           Byte _CheckSumByte = 0x00;
           for (int i = 0; i < PacketLength; i++)
               _CheckSumByte ^= _PacketData[i];
           return _CheckSumByte;
       }

Convert.ToString(0xf8 ^ 0x3f ^ 0x3f, 16);