使用实体框架创建一对多关系时遇到问题

Question

我已经看到很多关于这个问题的问题，但我找不到对我有帮助的问题，我试图在建筑物和房间之间建立一对多的关系，即一栋有很多房间的建筑物。据我所知，我的 ICollection 值没有发送到我的数据库。我正在使用局部视图在建筑物内创建房间，我的建筑物模型包含 Icollection，我的房间模型包含建筑物 ID。但是，当我创建一个房间时，它不会将 buildingId 与 ICollection 值连接起来。

这是我的建筑和房间模型：

public class buildingInfo
{
    public int Id { get; set; }
    public int buildingNumber { get; set; }
    public String buildingName { get; set; }
    public String buildingAddress { get; set; }
    public String buildingDesc { get; set; }
    public virtual ICollection<roomInfo> curRooms { get; set; }
}

public class roomInfo
{
    public int Id { get; set; }
    public int roomNumber { get; set; }
    public String roomName { get; set; }
    public String roomLocation { get; set; }
    public String roomDesc { get; set; }
    public int buildingId { get; set; }
}

这是房间视图：

 @model TerminalHost.Models.buildingInfo

@{
ViewBag.Title = "Home Page";
}
<h3>Rooms in: @Model.buildingName</h3>
<ol class="round">

<li class="one">
    <h5>Please begin creating your network structure:</h5> <button id="modal-opener">Add a new room</button>

</li>
</ol>

@Html.Partial("rooms", Model.curRooms)

<div id="Modal" title="Room Details">
    @Html.Partial("roomForm", new TerminalHost.Models.roomInfo { buildingId =  Model.Id })
</div>

这是包含房间详细信息的表格：

@model TerminalHost.Models.roomInfo

 <h2>Create</h2>

 @using (Html.BeginForm("roomForm","Home"))
{
@Html.AntiForgeryToken()
@Html.ValidationSummary(true)

<fieldset>
    <legend>roomInfo</legend>

    <div class="editor-label">
        @Html.Label("Room Number:")
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.roomNumber)
        @Html.ValidationMessageFor(model => model.roomNumber)
    </div>
    ....
    <div style="visibility: hidden">

        <div class="editor-field">
            @Html.TextBoxFor(model => model.buildingId)
            @Html.ValidationMessageFor(model => model.buildingId)
        </div>
    </div>
    <p>
        <input type="submit" value="Create" />
    </p>
 </fieldset>
 }
 @section Scripts {
   @Scripts.Render("~/bundles/jqueryval")
 }

这些是处理房间局部视图的方法：

 [HttpGet]
    public ActionResult roomForm(int buildingId)
    {
        return PartialView();
    }
    //Here the data from the room form is inserted to the database
    [HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult roomForm(roomInfo roominfo)
    {
        //roominfo.
        if (ModelState.IsValid)
        {
            _db.rooms.Add(roominfo);
            _db.SaveChanges();
            return RedirectToAction("room", new {id = roominfo.buildingId});
        }

        return PartialView(roominfo);
    }

这是 DBContext：

public class thDB : DbContext
{
    public DbSet<buildingInfo> buildings { get; set; }
    public DbSet<roomInfo> rooms { get; set; }
    public DbSet<deviceInfo> devices { get; set; }
    public DbSet<rackInfo> rackInfoes { get; set; }
} 

如果需要任何进一步的信息，请询问。

Answer 1

我认为 Entity Framework 无法通过其约定识别实体之间的正确外键，因为您的属性命名约定与 EF 期望的任何内容都不匹配。它可能会添加自己的外键，因此当您在 roomInfo 实体上设置 buildingId 时，它不会被视为外键。

您可以尝试在 DbContext 中添加一些实体映射配置来明确描述关系：

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<buildingInfo>().HasMany(b=>b.curRooms).WithRequired().HasForeignKey(r=>r.buildingId);
}

Answer 2

希望对你有帮助

public class buildingInfo
{

    public buildingInfo()
    {
        curRooms = new List<roomInfo>();

    }

    [Key]
    public int Id { get; set; }

    public int buildingNumber { get; set; }
    public String buildingName { get; set; }
    public String buildingAddress { get; set; }
    public String buildingDesc { get; set; }

    public virtual ICollection<roomInfo> curRooms { get; set; }
}

public class roomInfo
{

    public roomInfo()
    {
    }

    [Key]
    public int Id { get; set; }

    public int roomNumber { get; set; }
    public String roomName { get; set; }
    public String roomLocation { get; set; }
    public String roomDesc { get; set; }

    public virtual buildingInfo BuildingInfo { get; set; }
}