C#验证身份证的函数

这段C#代码主要是验证身份证的开头和身份证的格式和长度是否正确，没有按照身份证的编码规则进行严格验证

/// <summary>
   /// 验证身份证是否合法
   /// </summary>
   /// <param name="idCard">要验证的身份证</param>    
   public static bool IsIdCard(string idCard)
   {
     //如果为空，认为验证合格
     if (IsNullOrEmpty(idCard))
     {
       return true;
     }

//清除要验证字符串中的空格
     idCard = idCard.Trim();

//模式字符串
     StringBuilder pattern = new StringBuilder();
     pattern.Append(@"^(11|12|13|14|15|21|22|23|31|32|33|34|35|36|37|41|42|43|44|45|46|");
     pattern.Append(@"50|51|52|53|54|61|62|63|64|65|71|81|82|91)");
     pattern.Append(@"(\d{13}|\d{15}[\dx])$");

//验证
     return RegexHelper.IsMatch(idCard, pattern.ToString());
   }

更为复杂些的验证方法：

private string CheckCidInfo(string cid)
{
 string[] aCity = new string[]{null,null,null,null,null,null,null,null,null,null,null,"北京","天津","河北","山西","内蒙古",null,null,null,null,null,"辽宁","吉林","黑龙江",null,null,null,null,null,null,null,"上海","江苏","浙江","安微","福建","江西","山东",null,null,null,"河南","湖北","湖南","广东","广西","海南",null,null,null,"重庆","四川","贵州","云南","西藏",null,null,null,null,null,null,"陕西","甘肃","青海","宁夏","新疆",null,null,null,null,null,"台湾",null,null,null,null,null,null,null,null,null,"香港","澳门",null,null,null,null,null,null,null,null,"国外"};
 double iSum=0;
 string info="";
 System.Text.RegularExpressions.Regex rg = new System.Text.RegularExpressions.Regex(@"^\d{17}(\d|x)$");
 System.Text.RegularExpressions.Match mc = rg.Match(cid);
 if(!mc.Success)
 {
 return "";
 }  
 cid = cid.ToLower();
 cid = cid.Replace("x","a");
 if(aCity[int.Parse(cid.Substring(0,2))]==null)
 {
 return "非法地区";
 }
 try
 {
 DateTime.Parse(cid.Substring(6,4)+"-"+cid.Substring(10,2)+"-"+cid.Substring(12,2));
 }
 catch
 {
 return "非法生日";
 }
 for(int i=17;i>=0;i--)
 {  
 iSum +=(System.Math.Pow(2,i)％11)*int.Parse(cid[17-i].ToString(),System.Globalization.NumberStyles.HexNumber);

}
 if(iSum％11!=1)
 return("非法证号");

return(aCity[int.Parse(cid.Substring(0,2))]+","+cid.Substring(6,4)+"-"+cid.Substring(10,2)+"-"+cid.Substring(12,2)+","+(int.Parse(cid.Substring(16,1))％2==1&iexcl;"男":"女"));

}

调用测试：
Response.Write(CheckCidInfo("340524198002300019"));
Response.Write(CheckCidInfo("34052419800101001x"));

方法三：

/// <summary>
/// 身份证验证
/// </summary>
/// <param name="Id">身份证号</param>
/// <returns></returns>
public bool CheckIDCard(string Id)
{
 if (Id.Length == 18)
 {
    bool check = CheckIDCard18(Id);
    return check;
  }
  else if (Id.Length == 15)
  {
    bool check = CheckIDCard15(Id);
    return check;
  }
  else
  {
    return false;
  }
}
/// <summary>
/// 18位身份证验证
/// </summary>
/// <param name="Id">身份证号</param>
/// <returns></returns>
PRivate bool CheckIDCard18(string Id)
{
  long n = 0;
  if (long.TryParse(Id.Remove(17), out n) == false || n < Math.Pow(10, 16) || long.TryParse(Id.Replace('x', '0').Replace('X', '0'), out n) == false)
  {
    return false;//数字验证
  }
  string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
  if (address.IndexOf(Id.Remove(2)) == -1)
  {
    return false;//省份验证
  }
  string birth = Id.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 = Id.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] != Id.Substring(17, 1).ToLower())
  {
    return false;//校验码验证
  }
  return true;//符合GB11643-1999标准
}
/// <summary>
/// 15位身份证验证
/// </summary>
/// <param name="Id">身份证号</param>
/// <returns></returns>
private bool CheckIDCard15(string Id)
{
  long n = 0;
  if (long.TryParse(Id, out n) == false || n < Math.Pow(10, 14))
  {
    return false;//数字验证
  }
  string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
  if (address.IndexOf(Id.Remove(2)) == -1)
  {
    return false;//省份验证
  }
  string birth = Id.Substring(6, 6).Insert(4, "-").Insert(2, "-");
  DateTime time = new DateTime();
  if (DateTime.TryParse(birth, out time) == false)
  {
    return false;//生日验证
  }
  return true;//符合15位身份证标准
}

以上所述就是本文的全部内容了，希望大家能够喜欢。