byte[] ipadArray = new byte[64];
            byte[] opadArray = new byte[64];
            byte[] keyArray = new byte[64];
            System.Security.Cryptography.SHA1 sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider();

           // SHA1 sha1 = null;
            int ex = key.Length;
            if (key.Length > 64)
            {
                byte[] temp = sha1.ComputeHash(strToToHexByte(key));
                ex = temp.Length;
                for (int i = 0; i < ex; i++)
                {
                    keyArray[i] = temp[i];
                }
            }
            else
            {
                byte[] temp = strToToHexByte(key);
                for (int i = 0; i < temp.LongLength; i++)
                {
                    keyArray[i] = temp[i];
                }
            }

            for (int i = ex; i < 64; i++)
            {
                keyArray[i] = 0;
            }
            for (int j = 0; j < 64; j++)
            {
                ipadArray[j] = (byte)(keyArray[j] ^ 0x36);
                opadArray[j] = (byte)(keyArray[j] ^ 0x5C);
            }
            byte[] tempResult = sha1.ComputeHash(join(ipadArray, strToToHexByte(data)));

            return sha1.ComputeHash(join(opadArray, tempResult));

        }