public async Task <IActionResult> OnPostAsync() { var course = await _context.GetCourseAsync(Event.CourseID); await CheckRole(_context, _userManager, course.Pair.JoinCode); var success = await _context.DeleteEventAsync(Event.EventID); if (!success || !IsMentor) { return(RedirectToPage("/Error")); } return(RedirectToPage("/Mentor/Course/Index", new { id = Event.CourseID })); }