C#版18位身份证号码校验

public static bool CheckIDCard18(string IDCard)
        {
            //18位身份证号由6位的地区代码、8位的生日码、3位编号和1位的校验码组成。
            if (string.IsNullOrWhiteSpace(IDCard) || IDCard.Length != 18)
                return false;
            long n = 0;
            if (long.TryParse(IDCard.Remove(17), out n) == false || n < Math.Pow(10, 16) || long.TryParse(IDCard.Replace('x', '0').Replace('X', '0'), out n) == false)
            {
                return false;//数字验证  
            }
            string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
            if (address.IndexOf(IDCard.Remove(2)) == -1)
            {
                return false;//省份验证  
            }
            string birth = IDCard.Substring(6, 8).Insert(6, "-").Insert(4, "-");
            DateTime time = new DateTime();
            if (DateTime.TryParse(birth, out time) == false)
            {
                return false;//生日验证  
            }
            string[] arrVarifyCode = ("1,0,x,9,8,7,6,5,4,3,2").Split(',');
            string[] Wi = ("7,9,10,5,8,4,2,1,6,3,7,9,10,5,8,4,2").Split(',');
            char[] Ai = IDCard.Remove(17).ToCharArray();
            int sum = 0;
            for (int i = 0; i < 17; i++)
            {
                sum += int.Parse(Wi[i]) * int.Parse(Ai[i].ToString());
            }
            int y = -1;
            Math.DivRem(sum, 11, out y);
            if (arrVarifyCode[y] != IDCard.Substring(17, 1).ToLower())
            {
                return false;//校验码验证  
            }
            return true;//符合GB11643-1999标准  
        }