using System.Security.Cryptography;
public static void Main()
var url = "/batch/2022111114";
""transaction"": 6695646373,
Console.WriteLine(GetHMAC(text, key));
private static string GetHMAC(string text, string key)
using (var hmacsha256 = new HMACSHA256(Encoding.UTF8.GetBytes(key)))
var hash = hmacsha256.ComputeHash(Encoding.UTF8.GetBytes(text));
return Convert.ToHexString(hash).ToLower();