### Changing an IDate Object

You can add days to, or subtract days from, an IDate object. You can also subtract one date from another, in which case the result is the number of days between the two dates. For example:

    IDate Day1, Day2;
    int NumDays;
    Day1=IDate::today();
    Day2=Day1+1;              // Day2 is one day after Day1
    Day2+=2;                  // Day2 is now three days after Day1
    NumDays=Day2-Day1;        // NumDays=3

Note that you cannot add two IDate objects together, because such an addition does not make sense. However, you can add two ITime objects together.