public static string GetSHA256hash(string input, string _input_charset)

        {

            byte[] clearBytes = Encoding.UTF8.GetBytes(input);

            SHA256 sha256 = new SHA256Managed();

            sha256.ComputeHash(clearBytes);

            byte[] hashedBytes = sha256.Hash;

            sha256.Clear();

            string output = BitConverter.ToString(hashedBytes).Replace("-", "").ToLower();

            return output;

        }