所以我想展示一个饼图,并在 每天,为此,我想总结过去7天的每一天。 这就是我试图做的:
IEnumerable<DateTime> commentList;
commentList = await _context.Commentdb.Select(a => a.dateSubmit)
.GroupBy(b => b.Day).ToListAsync();
但它不起作用,而是显示此错误:
Cannot implicity convert type List<int,DateTime> to List<DateTime>
答案 0 :(得分:0)
您需要先按日期和日期进行分组。
IEnumerable<DateTime> commentList;
commentList = await _context.Commentdb.GroupBy(b => new { b.Day, b.dateSubmit }).Select(a => a.Key.dateSubmit)
.ToListAsync();
更新:
IEnumerable<DateTime> commentList;
commentList = await _context.Commentdb.Where(x => x.dateSubmit.DayOfWeek == DayOfWeek.Sunday ||x.dateSubmit.DayOfWeek == DayOfWeek.Saturday).GroupBy(b => new { b.Day, b.dateSubmit }).Select(a => a.Key.dateSubmit)
.ToListAsync();