我有以下课程:
public class Problem : AuditableTable
{
public Problem()
{
this.Questions = new List<Question>();
}
public int ProblemId { get; set; }
public string Title { get; set; }
public virtual ICollection<Question> Questions { get; set; }
}
public Question()
{
this.Answers = new List<Answer>();
}
public int QuestionId { get; set; }
public int ProblemId { get; set; }
public virtual ICollection<Answer> Answers { get; set; }
public virtual Problem Problem { get; set; }
}
public class Answer : AuditableTable
{
public int AnswerId { get; set; }
public int QuestionId { get; set; }
public string Text { get; set; }
public virtual Question Question { get; set; }
}
我想发出这样的查询:
var problems = _problemsRepository.GetAll()
.Where(p => p.ProblemId == problemId)
.Include(p => p.Questions)
.Include(p => p.Questions.Answers)
.ToList();
return problems;
所以我可以看到问题,问题和答案信息。但我的最后一个包含有一个问题,我无法弄清楚如何包含答案。
有人可以给我一些建议。
答案 0 :(得分:6)
这在EntityFramework 7.0中已更改。
新语法采用
形式var problems = _problemsRepository.GetAll()
.Where(p => p.ProblemId == problemId)
.Include(p => p.Questions)
.ThenInclude(q => q.Answers)
.ToList();
答案 1 :(得分:5)
您可以使用.Select()。
var problems = _problemsRepository.GetAll()
.Where(p => p.ProblemId == problemId)
.Include(p => p.Questions.Select(q => q.Answers))
.ToList();
现在你的答案将被包括在内。