specify current week based on day of week asp.net mvc 5 - asp.net

Question

Currently I'm trying to make a query that based on the day of week gets movies out of the database of that week.
So a movie week is from Thursday to next Wednesday.
When its Sunday, I only want movies from Sunday to Wednesday.
If its Tuesday, I only want movies from Tuesday to Wednesday etc.
I'm really getting stuck on what you can and cannot do in asp any suggestions?
Here's my code so far:
public IEnumerable<Viewing> GetUpcomingWeekViews()
{
var viewingList1 = _efdbContext.Viewing.ToList();
DateTime currentDate = DateTime.Now.Date;
var viewingList = _efdbContext.Viewing.ToList();
DateTime startOfWeek = DateTime.Now.
return viewingList.Where(v => (
v.StartTime.Date == currentDate.Date) &&
(v.StartTime.TimeOfDay > currentDate.TimeOfDay)
).OrderBy(v => v.StartTime);
}

Answer 1

Use the DayOfWeek property of DateTime:
var date = DateTime.Now;
var currentWeekday = (int)date.DayOfWeek;
const int wednesday = 3; // sunday is 0
var offset = 0;
// if today is before wednesday, go to next wednesday
if (currentWeekday < wednesday) {
offset = wednesday - currentWeekday;
}
// if today is wednesday, add a whole week till next wednesday
if(currentWeekday == wednesday) {
offset = 7;
}
// if today is after wednesday, go to wednesday in a week
if(currentWeekday > wednesday) {
offset = wednesday - currentWeekday + 7;
}
var nextWednesday = date.AddDays(offset);
Fiddle

Answer 2

First calculate the offset from Current date to desired date using DateOfWeek
public int CalculateOffset(DayOfWeek current, DayOfWeek desired) {
// f( c, d ) = [7 - (c - d)] mod 7
// f( c, d ) = [7 - c + d] mod 7
// c is current day of week and 0 <= c < 7
// d is desired day of the week and 0 <= d < 7
int c = (int)current;
int d = (int)desired;
int offset = (7 - c + d) % 7;
return offset == 0 ? 7 : offset;
}
And add that offset to the Date of the current DateTime
public IEnumerable<Viewing> GetUpcomingWeekViews(DayOfWeek desiredDayOfWeek = DayOfWeek.Thursday) {
DateTime minStartTime = DateTime.Now;
var currentDayOfWeek = minStartTime.DayOfWeek;
int offset = CalculateOffset(currentDayOfWeek, desiredDayOfWeek);
DateTime maxStartTime = minStartTime.Date.AddDays(offset);
var viewingList = dbContext.Viewing.ToList();
return viewingList
.Where(v => minStartTime <= v.StartTime && v.StartTime < maxStartTime)
.OrderBy(v => v.StartTime);
}