我有2个表（程序，外科医生）和一个查找表（ProcSurg）来创建多对多的关系。
scar_Requests scar_Procedures scar_ProcSurg scar_Surgeons
------------- --------------- ------------- -------------
RequestID <> ProcedureID <> ProcedureID(fk) <> SurgeonID
... RequestID SurgeonID(fk) ...
...
单个请求可以有多个程序，每个程序可以有多个外科医生。
一切都保存正确，直到我有两个共享同一个外科医生的程序。
Error: InvalidOperationException was unhandled
The relationship between the two objects cannot be defined because they are attached to different ObjectContext objects.
我将保存此部分记录的代码分离出来，试图找出我的问题..
Addprocedures是一个包含1个过程和外科医生列表的类
class Procedure
{
public scar_Procedures Procedure { get; set; }
public List<scar_Surgeons> Surgeons { get; set; }
public void RemoveSurgeon(int SurgeonID)
{
Surgeons.Remove(Surgeons.Where(x => x.SurgeonID == SurgeonID).FirstOrDefault());
}
public Procedure()
{
Surgeons = new List<scar_Surgeons>();
}
}
保存代码：使用DBContext
private void SaveProcSurg()
{
using (MCASURGContext db2 = new MCASURGContext())
{
foreach (Procedure p in AddProcedures)
{
if (p.Procedure.RequestID == 0)
{
p.Procedure.RequestID = ReqID;
}
p.Procedure.scar_Surgeons.Clear();
foreach (scar_Surgeons s in p.Surgeons)
{
if (db2.ChangeTracker.Entries<scar_Surgeons>().Where(x => x.Entity.SurgeonID == s.SurgeonID).FirstOrDefault() == null)
{
db2.scar_Surgeons.Attach(s);
}
p.Procedure.scar_Surgeons.Add(s);
}
if (p.Procedure.ProcedureID == 0)
{
db2.scar_Procedures.Add(p.Procedure);
db2.Entry(p.Procedure).State = System.Data.Entity.EntityState.Added;
}
else
{
db2.scar_Procedures.Attach(p.Procedure);
db2.Entry(p.Procedure).State = System.Data.Entity.EntityState.Modified;
}
}
db2.SaveChanges();
}
}
我尝试了几种保存记录的方法，这是我最接近正确的方法。
我觉得这与我将外科医生连接到实体然后再附加到手术的方式有关。关于我能找到答案的任何帮助，想法或建议都会很棒！
我一直在无休止地搜索谷歌超过一个星期，我一直在试图围绕实体框架正在做什么，但我仍然很新。
很抱歉，这是评论部分的完整代码段，其中包含req变量
//Internal variable
private scar_Requests req;
private List<Procedure> AddProcedures = new List<Procedure>();
//Gets a scar_Request from the DB
private void GetRequest()
{
using (MCASURGContext db = new MCASURGContext())
{
req = db.scar_Requests.Include("scar_Procedures.scar_Surgeons").Include("scar_Status").Include("scar_Users.scar_Service").Where(x => x.RequestID == ReqID).FirstOrDefault();
foreach (scar_Procedures p in req.scar_Procedures) { AddProcedures.Add(new Procedure() { Proc = p, Surgeons = p.scar_Surgeons.ToList() }); }
}
}
答案 0 :(得分：0)
保持良好状态我会发布我的回答，因为我认为我已经弄明白了。也许它会在将来帮助某人。
我完全重写了保存并删除了之前使用过的许多无用的代码，并减少了对DB的调用。还有其他方法我没有在上面发布，保存了我压缩成单一方法的记录的其他部分。
基本上我从DB获取记录及其连接表，并遍历需要更新的所有字段/连接表并将其保存回数据库。 （现在看起来非常明显，但我以前尝试过这种方式而且我一定有错误，因为我这样做的前几次没有工作。）
我不知道它的100％是否正确或是否符合正常的编码标准，并且在完成之前我还有一些最后的调整要做。
private void SaveProcSurg()
{
using (MCASURGContext db2 = new MCASURGContext())
{
//Get Record from DB
scar_Requests sReq = db2.scar_Requests.Include("scar_Users").Include("scar_Status").Include("scar_Procedures.scar_Surgeons").Where(x => x.RequestID == ReqID).FirstOrDefault();
//Update Record fields
sReq.CreationDate = req.CreationDate == null ? DateTime.Now : req.CreationDate = req.CreationDate;
sReq.DateOfSurgery = dtpDateOfSurgery.Value;
sReq.IsDeleted = false;
sReq.IsScheduled = false;
sReq.LatexAllergy = cbLatexAllergy.Checked;
sReq.ModifiedDate = DateTime.Now;
sReq.MRN = txtMRN.Text;
sReq.PatientName = txtPatientName.Text;
foreach (RadioButton rb in gbPatientType.Controls) if (rb.Checked == true) sReq.PatientType = rb.Text;
sReq.PreOpDiagnosis = txtPreOpDiag.Text;
sReq.PrimarySurgeon = txtPrimarySurgeon.Text;
sReq.PrivateComment = txtPrivateComment.Text;
sReq.PublicComment = txtPublicComment.Text;
sReq.RequestID = ReqID;
sReq.StatusID = req.StatusID;
sReq.UserID = req.UserID;
//Update Users/Status
sReq.scar_Users = db2.scar_Users.Where(x => x.UserID == sReq.UserID).FirstOrDefault();
sReq.scar_Status = db2.scar_Status.Where(x => x.StatusID == req.StatusID).FirstOrDefault();
//Attach to DBContext
db2.scar_Requests.Attach(sReq);
//Update Procedures
foreach (Procedure p in AddProcedures)
{
scar_Procedures pro = sReq.scar_Procedures.Where(x => x.ProcedureID == p.Proc.ProcedureID && p.Proc.ProcedureID != 0).FirstOrDefault();
if (pro != null)
{
pro.EnRecovery = p.Proc.EnRecovery;
pro.IsPrimary = p.Proc.IsPrimary;
pro.Laterality = p.Proc.Laterality;
pro.OrthoFastTrack = p.Proc.OrthoFastTrack;
pro.ProcedureID = p.Proc.ProcedureID;
pro.ProcedureText = p.Proc.ProcedureText;
pro.RequestID = ReqID;
pro.Site = p.Proc.Site;
}
else
{
pro = new scar_Procedures();
pro.EnRecovery = p.Proc.EnRecovery;
pro.IsPrimary = p.Proc.IsPrimary;
pro.Laterality = p.Proc.Laterality;
pro.OrthoFastTrack = p.Proc.OrthoFastTrack;
pro.ProcedureID = p.Proc.ProcedureID;
pro.ProcedureText = p.Proc.ProcedureText;
pro.RequestID = ReqID;
pro.Site = p.Proc.Site; ;
pro.scar_Requests = sReq;
}
//Update Surgeons
pro.scar_Surgeons.Clear();
foreach (scar_Surgeons s in p.Surgeons)
{
pro.scar_Surgeons.Add(db2.scar_Surgeons.Where(x=> x.SurgeonID == s.SurgeonID).FirstOrDefault());
}
}
//Set State and Save
db2.Entry(sReq).State = System.Data.Entity.EntityState.Modified;
db2.SaveChanges();
}
}