Utils.cs


using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

    public class Utils
    {
        public static string ByteToString(byte[] buff)
        {
            string sbinary = "";
            for (int i = 0; i < buff.Length; i++)
            {
                sbinary += buff[i].ToString("X2"); /* hex format */
            }
            return (sbinary);
        }

        public static string GenerateTimeStamp(DateTime baseDateTime)
        {
            var dtOffset = new DateTimeOffset(baseDateTime);
            return dtOffset.ToUnixTimeMilliseconds().ToString();
        }

        private static char[] HEX_DIGITS = new char[]{'0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
        /// <summary>
        /// 生成32位大写MD5值
        /// </summary>
        public static String getMD5String(String str)
        {

            if (str == null || str.Trim().Length == 0)
            {
                return "";
            }
            byte[] bytes = System.Text.Encoding.Default.GetBytes(str);
            MD5CryptoServiceProvider md = new MD5CryptoServiceProvider();
            bytes = md.ComputeHash(bytes);
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < bytes.Length; i++)
            {
                sb.Append(HEX_DIGITS[(bytes[i] & 0xf0) >> 4] + ""
                        + HEX_DIGITS[bytes[i] & 0xf]);
            }
            return sb.ToString();
        }

    

    public static long GetNonce()
        {
            return DateTime.Now.Ticks * 10 / TimeSpan.TicksPerMillisecond; // use millisecond timestamp or whatever you want
        }

        public static decimal percent(decimal value, decimal percent)
        {
            percent = percent / 100;
            return value + (percent * value);
        }

        public static string CalculateSignature(string text, string secretKey)
        {
            using (var hmacsha512 = new HMACSHA512(Encoding.UTF8.GetBytes(secretKey)))
            {
                hmacsha512.ComputeHash(Encoding.UTF8.GetBytes(text));
                return string.Concat(hmacsha512.Hash.Select(b => b.ToString("x2")).ToArray()); // minimalistic hex-encoding and lower case
            }
        }
    }