c# – 如何向ThenInclude添加where子句
发布时间:2020-12-15 08:21:49 所属栏目:百科 来源:网络整理
导读:我有3个实体: Questionnaire.cs: public class Questionnaire{ public int Id { get; set; } public string Name { get; set; } public ICollectionQuestion Questions { get; set; }} Question.cs: public class Question{ public int Id { get; set; }
我有3个实体:
Questionnaire.cs: public class Questionnaire { public int Id { get; set; } public string Name { get; set; } public ICollection<Question> Questions { get; set; } } Question.cs: public class Question { public int Id { get; set; } public string Text { get; set; } public ICollection<Answer> Answers { get; set; } } 和Answer.cs: public class Answer { public int Id { get; set; } public string UserId { get; set; } public string TextAnswer { get; set; } } 所以我用答案保存了调查问卷,但现在我想找回问题及其答案的过滤问卷.所以我为此写了linq,但它给我一个错误,有什么我做错了吗?这是一个例子: questionnaire = _context.Questionnaires.Include(qn => qn.Questions) .ThenInclude(question => question.Answers.Where(a => a.UserId == userId)) .FirstOrDefault(qn => qn.Id == questionnaireId); 而且我得到了
任何想法如何解决这个问题? 解决方法
不支持在Include或IncludeThen中过滤.使用选择创建投影:
questionnaire = _context.Questionnaires .Select(n => new Questionnaire { Id = n.Id,Name = n.Name,Questions = n.Questions.Select(q => new Question { Id = q.Id,Text = q.Text,Answers = q.Where(a => a.UserId == userId).ToList() }).ToList() }) .FirstOrDefault(qn => qn.Id == questionnaireId); 关于这个问题有一个github问题:https://github.com/aspnet/EntityFramework/issues/3474 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |