非静态方法需要目标

Question

你能帮我解决这个问题

Profile ProfileDoctor = _context.Profiles.SingleOrDefault(p => p.ProfileId == id);
Users UserUser = _context.Users.SingleOrDefault(d => d.UserName == User.Identity.Name);
Profile UserProfile = _context.Profiles.Where(t => t.UserId == UserUser.UserId).SingleOrDefaul(); <--- Non-static method requires a target 
Meetings meeting = new Meetings

Answer 1

您将获得空引用异常.它被称为非静态目标异常,因为LINQ使用反射.检查该行是否不返回null.当我UserUser试图调用该UserUser.UserId属性时,我的猜测是null .