Question

tl;dr;
How would you take StartDate-DateTime: Dec 10th 2011, EndDate-DateTime Jan 15th 2012, and determine whether or not Dec 1, Dec 9,Dec 17,Dec 25, Jan 1, and Jan 9 fit into that TimeSpan, Year excluded and get a Bool for each one?

I have a visual timespan consisting of a linear graph showing when a specific activity is active.

I am given an object with a start date, and an end date.

I have covered the timespan with a DIV having a red background representing 1/4 of each month, naming them JanQ1, JanQ2, etc..

These start off as visibility:hidden, but need to be altered in the event that the activity is active during the part of the year.

The problem I’m having is getting a true/false value that ignores the year being given.

For example, an event that goes from Dec 10th 2011 to Jan 15th 2012, I would want this result set:

DecQ1=False,
DecQ2=True,
DecQ3=True,
DecQ4=True,
JanQ1=True,
JanQ2=True,
JanQ3=False

Answer 1

Would a function like this work for you?

bool IsDateContained(DateTime startDate, DateTime endDate, int month, int day) {
    bool retVal = false;
    if (startDate < endDate) {
        do {
            if (startDate.Month == month && startDate.Day == day) {
                retVal = true;
                break;
            }
            startDate = startDate.AddDays(1);
        } while (startDate < endDate);
    } else {
        //crazy world!!
    }
    return retVal;
}