【原创】计算从1970年到现在累计的秒数

时间：2010-09-10 来源：天堂大鸟

没啥技术含量，只不过是在没事干，就把这个也记上，Windows下好像有这个api函数，但是在wince下用不了，所以还得自己封装一个。大体代码如下：

/*the seconds of round year = 3600*24*366 */
#define SECONDOFROUNDYEAR 31622400

/*the seconds of general year = 3600*24*365 */
#define SECONDOFYEAR 31536000

unsigned int SecondsFrom1970()
{
        SYSTEMTIME st;
        unsigned int tTemp=0;
        unsigned int tSecond=0;
        int month_s[2][12]={{31,28,31,30,31,30,31,31,30,31,30,31},
        {31,29,31,30,31,30,31,31,30,31,30,31}};
        int nDays=0;
        int nCount=0;
        int i;
        int j;

        GetLocalTime(&st);
        tSecond=st.wHour*3600+st.wMinute*60+st.wSecond;

        for (i=1970;i<st.wYear;++i)
        {
                if (IsRound(i))
                        ++nCount;
        }

        tTemp+=(st.wYear-1970-nCount)*SECONDOFYEAR+nCount*SECONDOFROUNDYEAR;

        if (st.wMonth>1)
        {
                if (IsRound(st.wYear))
                {
                        for (j=0;j<st.wMonth-1;++j)
                        {
                                tTemp+=month_s[1][j]*MAXSECONDOFDAY;
                        }
                        tTemp+=(st.wDay-1)*MAXSECONDOFDAY+tSecond;
                }
                else
                {
                        for (j=0;j<st.wMonth-1;++j)
                        {
                                tTemp+=month_s[0][j]*MAXSECONDOFDAY;
                        }
                        tTemp+=(st.wDay-1)*MAXSECONDOFDAY+tSecond;
                }
        }
        else
        {
                tTemp+=(st.wDay-1)*MAXSECONDOFDAY+tSecond;
        }

        return tTemp;
}

bool IsRound(int year)
{
        /*is round year?*/
        if((year%100)&&(year%4==0)) return 1;
        if((year%100==0)&&(year%400==0)) return 1;
        return 0;
}