csharp 随机字符串生成器和支付ReferenceNumber生成器

Posted 2021-05-12

   public static class ReferenceNumberBuilder
    {
        const string defaultChars = "abcdefghijklmnoprstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        private static Random random = new Random();
        public static string RandomString(int length)
        {
            return RandomString(null, length);
        }

        /// <summary>
        /// Generates a random string from the provided string characters
        /// </summary>
        /// <param name="chars">if you pass emtpy string or null defaultChars are provided "abcdefghijklmnoprstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"</param>
        /// <param name="length">the length of the random string to generate</param>
        /// <returns>random string from character set and length you have provided </returns>
        public static string RandomString(string chars, int length)
        {
            if (string.IsNullOrWhiteSpace(chars))
                chars = defaultChars;

            return new string(Enumerable.Repeat(chars, length)
              .Select(s => s[random.Next(s.Length)]).ToArray());
        }

        public static string NewReferenceNumber()
        {
            /* 
			Struktura reference SI:
			- na 1. in 2. mestu: konstanta SI
			- na 3. in 4. mestu: številka modela
			- od 5. do 26. mesta: vsebina modela, ki je sestavljena iz največ 22 znakov, od tega do 20
			številk in največ dva vezaja		
			
			Št. Modela		Vsebina modela (razdelitev polja (sklopi P) in pozicija kontrolnih številk (K) v modelu)	Število sklopov (P)
			01 				(P1 - P2 - P3) K 																			Obvezno 1, Dovoljeno 3					
			*/

            var randomString = RandomString("0123456789", 15);
            var controlNumber = ControlNumberModule11(randomString);
            return string.Format("SI01{0}{1}", randomString, controlNumber);
        }

        public static int ControlNumberModule11(string referenceNumber)
        {
            if (string.IsNullOrWhiteSpace(referenceNumber))
                throw new ArgumentOutOfRangeException("referenceNumber", "reference number should contain at least 1 character");

            Dictionary<char, int> conversionTable = new Dictionary<char, int>() {
                {'A' ,10},
                {'B' ,11},
                {'C' ,12},
                {'D' ,13},
                {'E' ,14},
                {'F' ,15},
                {'G' ,16},
                {'H' ,17},
                {'I' ,18},
                {'J' ,19},
                {'K' ,20},
                {'L' ,21},
                {'M' ,22},
                {'N' ,23},
                {'O' ,24},
                {'P' ,25},
                {'Q' ,26},
                {'R' ,27},
                {'S' ,28},
                {'T' ,29},
                {'U' ,30},
                {'V' ,31},
                {'W' ,32},
                {'X' ,33},
                {'Y' ,34},
                {'Z' ,35}};

            int ponder = 2;
            int sum = 0;
            int parsedValue = -1;

            for (var pos = (referenceNumber.Length - 1); pos > 0; pos--)
            {
                parsedValue = -1;
                var convertedValue =
                    int.TryParse($"{referenceNumber[pos]}", out parsedValue) ? parsedValue
                        : (conversionTable.ContainsKey(referenceNumber[pos]) ? conversionTable[referenceNumber[pos]] : 0);
                sum += (ponder * convertedValue);
            }

            int modulo = sum % 11;
            int controlNumber = 11 - modulo;
            controlNumber = controlNumber >= 10 ? 0 : controlNumber;

            return controlNumber;
        }
    }