C# function to verify ID card

/// <summary>
    /// Verify whether the ID card is legal    /// </summary>
    /// <param name="idCard">ID card to be verified</param>    public static bool IsIdCard(string idCard)
    {
      //If it is empty, the verification is considered qualified      if (IsNullOrEmpty(idCard))
      {
        return true;
      }
 
      //Clear the spaces in the string to be validated      idCard = ();
 
      //Mode string      StringBuilder pattern = new StringBuilder();
      (@"^(11|12|13|14|15|21|22|23|31|32|33|34|35|36|37|41|42|43|44|45|46|");
      (@"50|51|52|53|54|61|62|63|64|65|71|81|82|91)");
      (@"(\d{13}|\d{15}[\dx])$");
 
      //verify      return (idCard, ());
    }

private string CheckCidInfo(string cid)
 {
  string[] aCity = new string[]{null,null,null,null,null,null,null,null,null,null,null,"Beijing","Tianjin","Hebei","Shanxi","Inner *",null,null,null,null,null,"Liaoning","Jilin","Heilongjiang",null,null,null,null,null,null,null,"Shanghai","Jiangsu","Zhejiang","Anwei","Fujian","Jiangxi","Shandong",null,null,null,"Henan","Hubei","Hunan","Guangdong","Guangxi","Hainan",null,null,null,"Chongqing","Sichuan","Guizhou","Yunnan","Tibet",null,null,null,null,null,null,"Shaanxi","Gansu","Qinghai","Ningxia","*",null,null,null,null,null,"*",null,null,null,null,null,null,null,null,null,"Hongkong","Macao",null,null,null,null,null,null,null,null,"foreign"};
  double iSum=0;
  string info="";
   rg = new (@"^\d{17}(\d|x)$");
   mc = (cid);
  if(!)
  {
  return "";
  }  
  cid = ();
  cid = ("x","a");
  if(aCity[((0,2))]==null)
  {
  return "Illegal Area";
  }
  try
  {
  ((6,4)+"-"+(10,2)+"-"+(12,2));
  }
  catch
  {
  return "Illegal Birthday";
  }
  for(int i=17;i>=0;i--)
  {  
  iSum +=((2,i)%11)*(cid[17-i].ToString(),);

  }
  if(iSum%11!=1)
  return("Illegal Certificate Number");
  
  return(aCity[((0,2))]+","+(6,4)+"-"+(10,2)+"-"+(12,2)+","+(((16,1))%2==1¡"male":"female"));
 
 }

Call test：
(CheckCidInfo("340524198002300019"));
(CheckCidInfo("34052419800101001x"));

/// <summary>
/// ID card verification/// </summary>
/// <param name="Id">ID number</param>/// &lt;returns&gt;&lt;/returns&gt;
public bool CheckIDCard(string Id)
{
  if ( == 18)
  {
     bool check = CheckIDCard18(Id);
     return check;
   }
   else if ( == 15)
   {
     bool check = CheckIDCard15(Id);
     return check;
   }
   else
   {
     return false;
   }
 }
 /// &lt;summary&gt;
 /// 18-digit ID card verification /// &lt;/summary&gt;
 /// <param name="Id">ID number</param> /// &lt;returns&gt;&lt;/returns&gt;
 PRivate bool CheckIDCard18(string Id)
 {
   long n = 0;
   if (((17), out n) == false || n &lt; (10, 16) || (('x', '0').Replace('X', '0'), out n) == false)
   {
     return false;//Digital verification   }
   string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
   if (((2)) == -1)
   {
     return false;//Provincial verification   }
   string birth = (6, 8).Insert(6, "-").Insert(4, "-");
   DateTime time = new DateTime();
   if ((birth, out time) == false)
   {
     return false;//Birthday verification   }
   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 = (17).ToCharArray();
   int sum = 0;
   for (int i = 0; i &lt; 17; i++)
   {
     sum += (Wi[i]) * (Ai[i].ToString());
   }
   int y = -1;
   (sum, 11, out y);
   if (arrVarifyCode[y] != (17, 1).ToLower())
   {
     return false;//Check code verification   }
   return true;//Complied with GB11643-1999 standard }
 /// &lt;summary&gt;
 /// 15-digit ID card verification /// &lt;/summary&gt;
 /// <param name="Id">ID number</param> /// &lt;returns&gt;&lt;/returns&gt;
 private bool CheckIDCard15(string Id)
 {
   long n = 0;
   if ((Id, out n) == false || n &lt; (10, 14))
   {
     return false;//Digital verification   }
   string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
   if (((2)) == -1)
   {
     return false;//Provincial verification   }
   string birth = (6, 6).Insert(4, "-").Insert(2, "-");
   DateTime time = new DateTime();
   if ((birth, out time) == false)
   {
     return false;//Birthday verification   }
   return true;//Complied with the 15-digit ID card standard }