using System;
using System.Security.Cryptography;
using System.Text;

namespace HmacHD5
{
    public static class HMAC
    {
        public static string CalculateHMAC(string dataPayload, string configmationSequence)
        {
            if (String.IsNullOrWhiteSpace(dataPayload) || String.IsNullOrWhiteSpace(configmationSequence))
                return "";

            var data = Encoding.UTF8.GetBytes(dataPayload);
            // key
            var key = Encoding.UTF8.GetBytes(configmationSequence);

            // Create HMAC-MD5 Algorithm;
            var hmac = new HMACMD5(key);

            // Compute hash.
            var hashBytes = hmac.ComputeHash(data);

            // Convert to HEX string.
            return System.BitConverter.ToString(hashBytes).Replace("-", "").ToLower();
        }
    }
}