当用户输入完身份证号码的时候我们通常需要确认其真实性，下面的代码估计可以帮到您，试试看

// 匹配身份证号码
-(BOOL)isHxIdentityCard
{
     // 判断位数
     if ([self length] != 15 && [self length] != 18)
     {
          return NO;
     }
     
     NSString *carid = self;
     long lSumQT  =0;
     // 加权因子
     int R[] ={7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 };
     // 校验码
     unsigned char sChecker[11]={'1','0','X', '9', '8', '7', '6', '5', '4', '3', '2'};
     // 将15位身份证号转换成18位
     NSMutableString *mString = [NSMutableString stringWithString:self];
     if ([self length] == 15)
     {
          [mString insertString:@"19" atIndex:6];
          long p = 0;
          const char *pid = [mString UTF8String];
          for (int i=0; i<=16; i++)
          {
               p += (pid[i]-48) * R[i];
          }
          int o = p%11;
          NSString *string_content = [NSString stringWithFormat:@"%c",sChecker[o]];
          [mString insertString:string_content atIndex:[mString length]];
          carid = mString;
     }
     // 判断地区码
     NSString * sProvince = [carid substringToIndex:2];
     if (![self areaCode:sProvince])
     {
          return NO;
     }
     // 判断年月日是否有效
     // 年份
     int strYear = [[carid substringWithRange:NSMakeRange(6,4)] intValue];
     // 月份
     int strMonth = [[carid substringWithRange:NSMakeRange(10,2)] intValue];
     // 日
     int strDay = [[carid substringWithRange:NSMakeRange(12,2)] intValue];
     
     NSTimeZone *localZone = [NSTimeZone localTimeZone];
     NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
     [dateFormatter setDateStyle:NSDateFormatterMediumStyle];
     [dateFormatter setTimeStyle:NSDateFormatterNoStyle];
     [dateFormatter setTimeZone:localZone];
     [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
     NSDate *date=[dateFormatter dateFromString:[NSString stringWithFormat:@"%d-%d-%d 12:01:01",strYear,strMonth,strDay]];
     if (date == nil)
     {
          return NO;
     }
     const char *PaperId  = [carid UTF8String];
     // 检验长度
     if( 18 != strlen(PaperId)) return -1;
     // 校验数字
     for (int i=0; i<18; i++)
     {
          if ( !isdigit(PaperId[i]) && !(('X' == PaperId[i] || 'x' == PaperId[i]) && 17 == i) )
          {
               return NO;
          }
     }
     // 验证最末的校验码
     for (int i=0; i<=16; i++)
     {
          lSumQT += (PaperId[i]-48) * R[i];
     }
     if (sChecker[lSumQT%11] != PaperId[17] )
     {
          return NO;
     }
     return YES;
}

-(BOOL)areaCode:(NSString *)code
{
     NSMutableDictionary *dic = [[NSMutableDictionary alloc] init];
     [dic setObject:@"北京" forKey:@"11"];
     [dic setObject:@"天津" forKey:@"12"];
     [dic setObject:@"河北" forKey:@"13"];
     [dic setObject:@"山西" forKey:@"14"];
     [dic setObject:@"内蒙古" forKey:@"15"];
     [dic setObject:@"辽宁" forKey:@"21"];
     [dic setObject:@"吉林" forKey:@"22"];
     [dic setObject:@"黑龙江" forKey:@"23"];
     [dic setObject:@"上海" forKey:@"31"];
     [dic setObject:@"江苏" forKey:@"32"];
     [dic setObject:@"浙江" forKey:@"33"];
     [dic setObject:@"安徽" forKey:@"34"];
     [dic setObject:@"福建" forKey:@"35"];
     [dic setObject:@"江西" forKey:@"36"];
     [dic setObject:@"山东" forKey:@"37"];
     [dic setObject:@"河南" forKey:@"41"];
     [dic setObject:@"湖北" forKey:@"42"];
     [dic setObject:@"湖南" forKey:@"43"];
     [dic setObject:@"广东" forKey:@"44"];
     [dic setObject:@"广西" forKey:@"45"];
     [dic setObject:@"海南" forKey:@"46"];
     [dic setObject:@"重庆" forKey:@"50"];
     [dic setObject:@"四川" forKey:@"51"];
     [dic setObject:@"贵州" forKey:@"52"];
     [dic setObject:@"云南" forKey:@"53"];
     [dic setObject:@"西藏" forKey:@"54"];
     [dic setObject:@"陕西" forKey:@"61"];
     [dic setObject:@"甘肃" forKey:@"62"];
     [dic setObject:@"青海" forKey:@"63"];
     [dic setObject:@"宁夏" forKey:@"64"];
     [dic setObject:@"新疆" forKey:@"65"];
     [dic setObject:@"台湾" forKey:@"71"];
     [dic setObject:@"香港" forKey:@"81"];
     [dic setObject:@"澳门" forKey:@"82"];
     [dic setObject:@"国外" forKey:@"91"];
     if ([dic objectForKey:code] == nil) {
          return NO;
     }
     return YES;
}