Hear is ample how you can itrates through the date range using foreach in C#
for itrating you will need to first create a function which will convert the date range in inumaration formate so that you can itrates.
For this i have created the follwing function.
public IEnumerable<DateTime> EachDay(DateTime from, DateTime thru)
for (var day = from.Date; day.Date <= thru.Date; day = day.AddDays(1)) yield return day;
Now you can use the code like this.
foreach (DateTime day in EachDay(strartDate, EndDate)