C# HMACSHA1 加密

            HMACSHA1 hmacsha1 = new HMACSHA1();
            hmacsha1.Key = Encoding.UTF8.GetBytes(secret);
            byte[] dataBuffer = Encoding.UTF8.GetBytes(mk); 
            byte[] hashBytes = hmacsha1.ComputeHash(dataBuffer);
            return Convert.ToBase64String(hashBytes);