Question

我有以下代码：

//
        // POST: /PlayRoundHole/Create

        [AcceptVerbs(HttpVerbs.Post)]
        public ActionResult Create(FormCollection collection)
        {
            try
            {
                DB db = new DB();

                PlayRound playRound = new PlayRound();
                playRound.PlayerID = Int64.Parse(Request.Form["Value"]);
                playRound.TenantID = 1;
                playRound.RoundID = Int64.Parse(Request.Form["RoundID"].ToString());
                playRound.Score = 0;

                var playRoundHoles = from prh in db.PlayRoundHoles.ToList()
                                     from hl in db.Holes.ToList()
                                     where prh.HoleID == hl.HoleID
                                     where prh.PlayRoundID == Int64.Parse(Request.Form["RoundID"].ToString())
                                     select new { prh.HoleID, hl.Sequence };
                foreach(var a in playRoundHoles)
                {
                    PlayRoundHole playRoundHole = new PlayRoundHole();
                    playRoundHole.HoleID = a.HoleID;
                    playRoundHole.Stroke = Byte.Parse(Request.Form["PlayRoundHoleID_" + a.Sequence].ToString());
                    playRound.PlayRoundHoles.Add(playRoundHole);
                }
                db.SubmitChanges();

                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }

根本没有错误但是我看不到正在保存的数据。有任何想法吗？无论如何要跟踪这个吗？

Answer 1

由于您的新对象未链接到datacontext（db），因此不会保存任何内容。如果您希望将新的PlayRound实例及其PlayRoundHole子项持久保存到数据库，则需要调用以下内容：

db.PlayRounds.InsertOnSubmit(playRound);
db.SubmitChanges();

在旁注中，以下查询从数据库中获取所有PlayRoundHoles和所有洞，然后然后在应用程序中过滤它们。

var playRoundHoles = from prh in db.PlayRoundHoles.ToList()
                     from hl in db.Holes.ToList()
                     where prh.HoleID == hl.HoleID
                     where prh.PlayRoundID == 42
                     select new { prh.HoleID, hl.Sequence };

你可能想要的是：

var playRoundHoles = from prh in db.PlayRoundHoles
                     from hl in db.Holes
                     where prh.HoleID == hl.HoleID
                     where prh.PlayRoundID == 42
                     select new { prh.HoleID, hl.Sequence };

这只会获取匹配的孔，而不是从两个表中获取完整的行，它只会获取HoleID和序列号。

用linq看不到保存数据？

1 个答案: