How many times a timespan occurs between two Datetimes

----EDIT----

Oh im sorry that was a huge misstake :)

Let me ask the question again...

Heres an example,

Datetime startTime = 2011-10-08 12:30:00
Da开发者_如何学JAVAtetime endTime = 2011-10-10 15:00:00

How many times does 12:00:00 - 13:00:00 occur between the two datetimes?

2011-10-08 12:30:00 - 2011-10-08 13:00:00 Not Ok (time has alredy started)
2011-10-09 12:00:00 - 2011-10-09 13:00:00 Ok
2011-10-10 12:00:00 - 2011-10-10 13:00:00 Ok

Expecting result 2.

Thanks in advance!

(endTime-startTime).Ticks/timeSpan.Ticks

After seeing your update you will want to do something like determine the days to check and do a bounds check to see if the times specific fall within your start and end dates. As an idea, here is some sample code I threw together.

    private static void CheckTimes()
    {
        DateTime start = DateTime.Parse("2011-10-08 12:30:00");
        DateTime end = DateTime.Parse("2011-10-10 15:00:00");
        // variable to use for bound checking (Date property sets the hour to 00)
        DateTime boundscheck = start.Date;
        // variable containing results
        int timesFound = 0;

        // This loop assumes we are only looking for one match per day
        for (int i = 0; i <= (end - start).Days; i++)
        {
            // set the lower bound to yyyy-mm-dd 12:00:00
            var lowerbound = boundscheck.Date.AddHours(12);
            // set the upper bound to yyyy-mm-dd 13:00:00
            var upperbound = lowerbound.AddHours(1);
            //determine if bounds are within our start and end date
            if (lowerbound >= start && upperbound <= end)
            {
                timesFound++;
            }
            // increment boundscheck variable by one day
            boundscheck = boundscheck.AddDays(1);
        }
    }

Hope this helps.

Take the difference of the two days, divided by the interval.

TimeSpan timeSpan = new TimeSpan(24, 00, 00); // one day

DateTime start = new DateTime(2011, 10, 08, 11, 00, 00);
DateTime end = new DateTime(2011, 10, 10, 23, 00, 00); // 2 and 1/2 days later

var occurances = ((end - start).Ticks / (float)timeSpan.Ticks); // 2.5f