COleDateTime mDate1(year1, month1, day1, hour1, min1, sec1);
COleDateTime mDate2(year2, month2, day2, hour2, min2, sec2);
COleDateTimeSpan mDateSpan=mDate2-mDate1;
double daysdiff = (double)mDateSpan;
COleDateTime mDate2(year2, month2, day2, hour2, min2, sec2);
COleDateTimeSpan mDateSpan=mDate2-mDate1;
double daysdiff = (double)mDateSpan;
参阅:The MFC Programing Reference 244页