Question

I was suggested from a friend the following code

var tmp = from allCourses in _db.tblCourseNeededHours orderby allCourses.tblCourse.CourseName where allCourses.Semester == semester select allCourses;

return tmp.Sum(x => x.NeededHoursPerWeek);

but i am receving this error

Cannot implicitly convert type ‘double’ to ‘System.Linq.IQueryable

Any idea how to fix it?

public IQueryable FindSumAllCourseNeededHoursInSemester(string semester)

Answer 1

Chris is correct if you want the complete total, if you want it by course name use GroupBy:

var hours = FindAllCourseNeededHoursInSemester(mySemester)
    .GroupBy(g => g.CourseName)
    .Select(c => new { c.Key, c.Sum(a => a.NeededHours) } );