使用實體框架創建一對多關係的問題

Question

我在這個問題上看到了很多問題，但我找不到幫助我的問題，我嘗試在建築物和房間之間創建一對多關係，即一個建築物與許多房間。據我所知，我的ICollection <>值沒有被髮送到我的數據庫。我使用局部視圖在建築物內部創建房間，我的建築物模型包含Icollection，而我的房間模型包含建築物ID。但是，當我創建一個房間時，它不會將buildingId與ICollection值相關聯。

這裏是我的模型的建築和房間都：

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; } 
} 

這房間查看：

@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> 

下面是發生在室內形式詳情：

@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") 
} 

這些是處理房間局部視圖的方法：

[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); 
    } 

這裏是的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; } 
} 

如果有任何進一步的信息需要請詢問。

Answer 1

我認爲實體框架無法通過其約定識別實體之間的正確外鍵，因爲您的屬性命名約定與EF預期的內容不匹配。它可能會添加它自己的外鍵，所以當您在roomInfo實體上設置buildingId時，它不會被當作外鍵處理。

你可以嘗試添加在你的DbContext一些實體映射配置明確描述這種關係：

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

Answer 2

希望這有助於

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; } 
}