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我在类之间有一个简单的关系 m:m Thing，People但是我的解决方案在更新记录时需要删除以前的记录，然后创建新的记录

例子：

我的桌子

  • 人员（人员 ID、姓名）
  • 事物（事物 ID、名称）
  • PeopleHasThing (PeopleId, ThingId)

我的模特

人模型.cs

    // The following method works!
    // I've tried but I have my doubts about deleting records
    public static void Update(PeopleModel p)
    {
        using (_context = new myDataContext())
        {
            var result = (from r in _context.People
                         where r.PeopleId == p.PeopleId
                         select r).SingleOrDefault();
            
            if (null == result) return;

            result.Name = p.Name;

            PeopleHasThing.DeleteAllByPeopleId(result.PeopleId);

            EntitySet<PeopleHasThing> set = new EntitySet<PeopleHasThing>();

            //HasThing = List<ThingModel>
            //ThingModel: { (Int32)ThingId, (bool)IsMarked. (string)Description }

            m.HasThing.ForEach(e =>
            {
                if (e.IsMarked)
                {
                    set.Add(new PeopleHasThing
                    {
                        ThingId = e.ThingId,
                        People = result
                    });
                }
            });

            result.PeopleHasThing = set;

            _context.SubmitChanges();
        }
    }

啊，问题是如何正确更新 M:N 关系？

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