用C#简单实现的36进制转换代码

private const string initValue = "A0000001";

        private static string cs = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

        public static string AddOne(string str)
        {
            if (str == string.Empty)
            {
                return initValue;
            }
            Int64 num = StringToNumber(str);
            return NumberToString(++num);
        }

        public static Int64 StringToNumber(string str)
        {
            int leg = str.Length;
            double num = 0;
            if (leg != 0)
            {
                for (int i = 0; i < leg; i++)
                {
                    if (str[i] != ‘0‘)
                    {
                        num += cs.IndexOf(str[i]) * Math.Pow(36, leg - 1 - i);
                    }
                }
            }
            return Convert.ToInt64(num);
        }

        public static string NumberToString(Int64 num)
        {
            string str = string.Empty;
            while (num >= 36)
            {
                str = cs[(int)(num % 36)] + str;
                num = num / 36;
            }
            return cs[(int)num] + str;
        }