[Unity] Verify the validity of the ID number

Use a character string to verify the validity of the 18-digit ID number.

 

Verification rules (principles):

 

 

 Code:

//校验身份证号
public static bool CheckIDCard18(string str)
{
   if (str.Length < 18) return false;

   string number17 = str.Substring(0, 17);
   string pattern = @"^\d*$";
   if (!Regex.IsMatch(number17, pattern)) return false;

   string number18 = str.Substring(17);
   string check = "10X98765432";
   int[] num = { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 };
   int sum = 0;
   for (int i = 0; i < number17.Length; i++)
   {
        sum += Convert.ToInt32(number17[i].ToString()) * num[i];
   }
   sum %= 11;
   if (number18.Equals(check[sum].ToString(), StringComparison.OrdinalIgnoreCase))
   {
      return true;
   }
   else
   {
      return false;
   }

}