Asp.net core 是否可以使用相同的_context.SaveChangesAsync（）添加父记录和子记录

我有以下两个父/子对象：-

 public Submission()
        {
            SubmissionQuestionSubmission = new HashSet<SubmissionQuestionSubmission>();
        }

        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Npi { get; set; }
        public bool Independent { get; set; }
        public string Comment { get; set; }

        public virtual ICollection<SubmissionQuestionSubmission> SubmissionQuestionSubmission { get; set; }
    }


public partial class SubmissionQuestionSubmission
    {
        public int SubmissionQuestionId { get; set; }
        public int SubmissionId { get; set; }
        public string Answer { get; set; }

        public virtual Submission Submission { get; set; }
    }

我创建了以下视图模型：-

 public class SubmissionCreate
    {
        public Submission Submission {set; get;}
        public IList<SubmissionQuestion> SubmissionQuestion { set; get; }

        public IList<SubmissionQuestionSubmission> SubmissionQuestionSubmission { set; get; }

    }

如果我有以下操作方法来添加父记录提交和子记录提交QuestionSubmission，但要这样做，我必须向数据库发出2个保存请求，一个保存父记录并获取其ID，另一个保存子记录并为其分配父ID，如下所示：-

public async Task<IActionResult> Create(SubmissionCreate sc)//Bind("Id,FirstName,LastName,Npi,Independent,Comment")]
        {
            if (ModelState.IsValid)
            {
              var newsubmission  =  _context.Submission.Add(sc.Submission);
                await _context.SaveChangesAsync();
                foreach (var v in sc.SubmissionQuestionSubmission)
                {

                    v.SubmissionId = sc.Submission.Id;
                    _context.SubmissionQuestionSubmission.Add(v);
                        }
                await _context.SaveChangesAsync();
                TempData["message"] = "Thank You.. Your request has been submitted...";
                return View("Confirmation");
            }
            return View(sc);
        }

所以我的问题是，我是否可以使用一个save语句而不是两个save语句来完成上述工作？

您不需要使用两个SaveChanges。您可以将newsubmission分配到Submission属性，而不是v.SubmissionId=sc.Submission.Id

在这种情况下，Id和ForeignKey由EF Core自动创建

var newsubmission=_context.Submission.Addsc.Submission； sc.SubmissionQuestionSubmission中的foreach var v { v、 提交=新提交； _context.SubmissionQuestionSubmission.Addv； } wait_context.SaveChangesAsync； 另一种方式

sc.Submission.SubmissionQuestionSubmission=新列表； sc.SubmissionQuestionSubmission中的foreach var v { sc.Submission.SubmissionQuestionSubmission.Addv } _context.Submission.Addsc.Submission； wait_context.SaveChangesAsync；