大陆身份证号码格式校验代码

最近项目用到身份证校验，在提交公安系统做实名校验前，需要自己检查一下身份证格式是否正确；毕竟每查询一次需要money啊；
提前排除用户随手输入的号码。因此贴出了分享一下

#ifndef __YSP_IDCARD_H__
#define __YSP_IDCARD_H__

#include <string>
#include <stdlib.h>
#include <ctype.h>
#include <time.h>

using namespace std;
namespace NS_YSP
{
// wi  =2(n-1)(mod 11)
static int32_t wi[18] = { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2, 1 };

// verify digit
static char vi[11] = {  '1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2'  };

class IDCard
{
    public:
        //身份证号码校验
        static int32_t verify(string idcard, int32_t& gender/*0: 女 1::表示男*/)
        {
            //把15位身份证升级为18位
            if  ( idcard.length() == 15)
            {
                idcard = uptoeighteen(idcard);
            }

            if  (idcard.length() != 18)
            {
                return -1;
            }

            //1-17必须是数字
            for(int32_t i = 0; i  < 17; ++i)
            {
                if( idcard[i] < '0' || idcard[i] > '9')
                {
                    return -2;
                }
            }

            //最后一位(第18位)为校验码，检查checksum值
            char verify = toupper(idcard[17]);
            if  (verify != checksum(idcard))
            {
                return -3;
            }

            //第1-2位为省级行政区划代码，[11, 65] (第一位华北区1，东北区2，华东区3，中南区4，西南区5，西北区6)
            string strProvince  = idcard.substr(0, 2);
            int32_t nProvince = atoi(strProvince.c_str());
            if( nProvince < 11 || nProvince > 65 )
            {
                return -4;
            }

            //第3-4为为地级行政区划代码，第5-6位为县级行政区划代码因为经常有调整，这块就不做校验

            //第7-10位为出生年份；//第11-12位为出生月份 //第13-14为出生日期
            if( !checkdate(idcard.substr(6,8)) )
            {
                return -5;
            }

            //第15-17位为顺序码，表示在同一地址码所标识的区域范围内，对同年、同月、同日出生的人编定的顺序号，顺序码的奇数分配给男性，偶数分配给女性
            string strSeq  = idcard.substr(14,3);
            int32_t nSeq = atoi(strSeq.c_str());
            gender = nSeq%2;

            return 0;
        }

        static bool checkdate(const string& strDate)
        {
            string strYear  = strDate.substr(0, 4);
            int32_t nYear = atoi(strYear.c_str());

            time_t timep;
            time(&timep);
            struct tm *p  = gmtime(&timep);
            if( p )
            {
                if( nYear < 1900 || nYear > 1900 + p->tm_year )
                {
                    return false;
                }

                if( atoi(strDate.c_str()) > (  (1900 + p->tm_year)*10000 + p->tm_mon*100 + p->tm_mday ) )
                {
                    return false;
                }
            }

            string strMon  = strDate.substr(4, 2);
            int32_t nMon = atoi(strMon.c_str());
            if( nMon <= 0  || nMon > 12 )
            {
                return false;
            }

            //月份天数表
            int32_t days[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
            bool bLeapYear =  (nYear % 4  == 0 && nYear % 100 != 0) ||  (nYear % 400  == 0);
            if( bLeapYear )
            {
                days[1] = 29;
            }
            string strDay  = strDate.substr(6, 2);
            int32_t nDay = atoi(strDay.c_str());
            if( nDay > days[nMon - 1 ]  || nDay <= 0 )
            {
                return false;
            }

            return true;
        }

        //计算校验码
        static char checksum(string eightcardid)
        {
            int32_t remaining = 0;
            int32_t ai[18];

            if  ( eightcardid.length() == 18  )
            {
                eightcardid = eightcardid.substr(0, 17);
            }

            if  ( eightcardid.length() == 17  )
            {
                int32_t sum = 0;
                for  (int32_t i = 0; i < 17; i++)
                {
                    string k  = eightcardid.substr(i, 1);
                    ai[i] = atoi(k.c_str());
                }

                for  (int32_t i = 0; i < 17; i++)
                {
                    sum = sum  + wi[i] * ai[i];
                }
                remaining = sum  % 11;
            }

            return vi[remaining];
        }

        //把15位身份证升级到18位身份证号码
        static string uptoeighteen(const string& fifteencardid)
        {
            string eightcardid  = fifteencardid.substr(0, 6);
            //加上年月日
            eightcardid = eightcardid  + "19";
            eightcardid = eightcardid  + fifteencardid.substr(6) ;
            //加上校验码
            eightcardid.push_back(checksum(eightcardid));
            return eightcardid;
        }
};

}

#endif