如何将主 ID 传递给详细外键？

Question

我有一个主从编辑没有按预期工作。

TaBarHeader - master 和 TaBarBody - detail，一对多关系：

public partial class TaBarHeader
   {
        [Key]
        public int Id { get; set; }
        public string ListaOtf { get; set; }
        public IEnumerable<TaBarBody> TaBarBodies { get; set; }
        public IEnumerable<TaBarTelegrama> TaBarTelegramas { get; set; }
  }

public partial class TaBarBody
   {
        [Key]
        public int Id { get; set; }
        public string Codstatie1 { get; set; }
        public int BarHeaderId { get; set; }
        [ForeignKey("BarHeaderId")]
        public TaBarHeader BarHeaderFk { get; set; }
   }

HeaderTelegrama/Details.cshtml:

@model TraficAlert.Models.ViewModels.HeaderTelegramaViewModel
        <dt class="col-sm-2">
          @Html.DisplayNameFor(model => model.TaBarHeader.ListaOtf)
        </dt>
        <dd class="col-sm-10">
          @Html.DisplayFor(model => model.TaBarHeader.ListaOtf)
        </dd>
(...)
          <th>
              @Html.DisplayNameFor(model => model.TaBarBody.Codstatie1)
          </th>

        @foreach (var item in Model.TaBarHeader.TaBarBodies)
        {
           <tr>
              <td>
                  @Html.DisplayFor(modelItem => item.Codstatie1)
              </td>

<a asp-controller="BodyTelegrama" asp-action="Edit" asp-route-id="@item.Id">Edit</a>

BodyTelegrama/Edit.cshtml:

@model TraficAlert.Models.ViewModels.BodyTelegramaViewModel
@{
    ViewData["Title"] = "Edit";
}

<h1>Edit</h1>

<h4>TaBarBody</h4>
<hr />
<div class="row">
    <div class="col-md-4">
        <form asp-action="Edit">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
<div class="form-group">
                <label asp-for="@Model.TaBarBody.Codstatie1" class="control-label">Cod Statie 1</label>
                <input asp-for="@Model.TaBarBody.Codstatie1" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.Codstatie1" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.Codstatie2" class="control-label">Cod Statie 2</label>
                <input asp-for="@Model.TaBarBody.Codstatie2" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.Codstatie2" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.DtIniP" class="control-label">Data Ini P</label>
                <input asp-for="@Model.TaBarBody.DtIniP" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.DtIniP" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.DtFinP" class="control-label">Data Fin P</label>
                <input asp-for="@Model.TaBarBody.DtFinP" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.DtFinP" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.DtIniR" class="control-label">Data Ini R</label>
                <input asp-for="@Model.TaBarBody.DtIniR" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.DtFinP" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.DtFinR" class="control-label">Data Fin R</label>
                <input asp-for="@Model.TaBarBody.DtFinR" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.DtFinR" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.KmIni" class="control-label">Km Ini</label>
                <input asp-for="@Model.TaBarBody.KmIni" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.KmIni" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.KmFin" class="control-label">Km Fin</label>
                <input asp-for="@Model.TaBarBody.KmFin" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.KmFin" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.LiniaFir" class="control-label">Linia Fir</label>
                <input asp-for="@Model.TaBarBody.LiniaFir" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.LiniaFir" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.NomImpactId" class="control-label">Impact</label>
                <select asp-for="@Model.TaBarBody.NomImpactId" class="form-control" asp-items="ViewBag.NomImpactId"></select>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.NomAnulatId" class="control-label">Anulat</label>
                <select asp-for="@Model.TaBarBody.NomAnulatId" class="form-control" asp-items="ViewBag.NomAnulatId"></select>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.MotivAnulare" class="control-label">Motiv Anulare</label>
                <input asp-for="@Model.TaBarBody.MotivAnulare" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.MotivAnulare" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="@Model.TaBarBody.Ruta" class="control-label">Ruta</label>
                <input asp-for="@Model.TaBarBody.Ruta" class="form-control" />
                <span asp-validation-for="@Model.TaBarBody.Ruta" class="text-danger"></span>
            </div>
            <div class="form-group">
                <input type="submit" asp-route-id="@ViewBag.TelegramaId" value="Save" />
            </div>
        </form>
    </div>
</div>

<div>
    <a asp-action="Index">Back to List</a>
</div>

BodyTelegramaController:

// GET
    public IActionResult Edit(int id, int HeaderTelegramaId)
    {
        BodyTelegramaViewModel bodyTelegramaViewModel = new BodyTelegramaViewModel();
        bodyTelegramaViewModel.TaBarBody = new TaBarBody();
        bodyTelegramaViewModel.TaBarBody.BarHeaderFk = new TaBarHeader();
        bodyTelegramaViewModel.TaBarBody = _unitofwork.BarBody.DetailsBarB(id);
        bodyTelegramaViewModel.TaBarBody.BarHeaderFk = _unitofwork.BarHeader.DetailsBarHB(id);

        ViewData["TelegramaId"] = HeaderTelegramaId;

        if (bodyTelegramaViewModel.TaBarBody == null)
        {
            return NotFound();
        }
        ViewData["NomImpactId"] = new SelectList(_unitofwork.NomImpact.GetAll(), "Id", "Nume");
        ViewData["NomAnulatId"] = new SelectList(_unitofwork.NomAnulat.GetAll(), "Id", "Nume");

        return View(bodyTelegramaViewModel);
    }


// POST
    public IActionResult Edit(int id, BodyTelegramaViewModel bodyTelegramaViewModel)
    {
        if (id != bodyTelegramaViewModel.TaBarBody.Id)
        {
            return NotFound();
        }

        if (ModelState.IsValid)
        {
            try
            {
                bodyTelegramaViewModel.TaBarBody.BarHeaderId = id;
                _unitofwork.BarBody.Update(bodyTelegramaViewModel.TaBarBody);
                _unitofwork.Save();
    }
            catch (DbUpdateConcurrencyException)
            {
                if (!TaBarBodyExists(bodyTelegramaViewModel.TaBarBody.Id))
                {
                    return NotFound();
}
                else
                {
                    throw;
                }
            }
            return RedirectToAction("Index");
        }
        return View(bodyTelegramaViewModel);
    }

每次我编辑记录时，我的外键 - BarHeaderId - 将其值更改为 0。

我试过 bodyTelegramaViewModel.TaBarBody.BarHeaderId = bodyTelegramaViewModel.TaBarHeader.Id; 但我收到错误 'Object reference not set to an instance of an object.'

如何获取 TaBarHeader.Id 值并将其放入 TaBarBody.BarHeaderId？

更新:

视图模型：

public class HeaderTelegramaViewModel
{
    public TaBarHeader TaBarHeader { get; set; }
    public IEnumerable<TaBarHeader> taBarHeader { get; set; }
    public TaBarBody TaBarBody { get; set; }
    public IEnumerable<TaBarBody> taBarBody { get; set; }
}

public class BodyTelegramaViewModel
{
    public TaBarBody TaBarBody { get; set; }
    public IEnumerable<TaBarBody> taBarBody { get; set; }
}

HeaderTelegramaController:

    public IActionResult Details(int id)
    {
        HeaderTelegramaViewModel headerTelegramaViewModel = new HeaderTelegramaViewModel();
        headerTelegramaViewModel.TaBarHeader = _unitofwork.BarHeaderRepository.DetailsBarHB(id);

        if (headerTelegramaViewModel == null)
        {
            return NotFound();
        }
        return View(headerTelegramaViewModel);
    }

BodyTelegramaController:

// GET
public IActionResult Edit(int id)
{
    BodyTelegramaViewModel bodyTelegramaViewModel = new BodyTelegramaViewModel();
    bodyTelegramaViewModel.TaBarBody = new TaBarBody();
    bodyTelegramaViewModel.TaBarBody.BarHeaderFk = new TaBarHeader();
    bodyTelegramaViewModel.TaBarBody = _unitofwork.BarBodyRepository.DetailsBarB(id);
    bodyTelegramaViewModel.TaBarBody.BarHeaderFk = _unitofwork.BarHeaderRepository.DetailsBarHB(id);
    return View(bodyTelegramaViewModel);
}

这些是方法 DetailsBarB() 和 DetailsBarHB():

    public TaBarBody DetailsBarB(int id)
    {
        return _db.TaBarBodies
            .Include(t => t.BarHeaderFk)
            .FirstOrDefault(m => m.Id == id);
    }

    public TaBarHeader DetailsBarHB(int id)
    {
        return _db.TaBarHeaders
        .Include(x => x.TaBarBodies).ThenInclude(x => x.BarHeaderFk.CategoriaFk)
        .FirstOrDefault(m => m.Id == id);
    }

Answer 1

您可以进行以下更改以获取 TaBarHeader ID。

在您的 Details View 中，将其更改为：

 <a asp-controller="BodyTelegrama" asp-action="Edit" asp-route-id="@item.Id" asp-route-HeaderTelegramaId="@Model.TaBarHeader.Id">Edit</a>

在您的 Edit 操作中，将其更改为：

public IActionResult Edit(int id,int HeaderTelegramaId)
{
    BodyTelegramaViewModel bodyTelegramaViewModel = new BodyTelegramaViewModel();
    bodyTelegramaViewModel.TaBarBody = new TaBarBody();
    bodyTelegramaViewModel.TaBarBody.BarHeaderFk = new TaBarHeader();
    bodyTelegramaViewModel.TaBarBody = _unitofwork.BarBodyRepository.DetailsBarB(id);
    bodyTelegramaViewModel.TaBarBody.BarHeaderFk = _unitofwork.BarHeaderRepository.DetailsBarHB(id);

    ViewData["TelegramaId"] = HeaderTelegramaId;

    return View(bodyTelegramaViewModel);
}
[HttpPost]
public IActionResult Edit(int id, BodyTelegramaViewModel bodyTelegramaViewModel)
{
 bodyTelegramaViewModel.TaBarBody.BarHeaderId = id;
 _unitofwork.BarBodyRepository.Update(bodyTelegramaViewModel.TaBarBody);
 _unitofwork.Save();
 return View(bodyTelegramaViewModel);
}

然后在您的 Edit View 中将其更改为：

<form asp-action="Edit">
<div asp-validation-summary="ModelOnly" class="text-danger"></div>

<div class="form-group">
    <input type="hidden" asp-for="@Model.TaBarBody.Id" />
    <label asp-for="@Model.TaBarBody.Codstatie1" class="control-label">Cod Statie 1</label>
    <input asp-for="@Model.TaBarBody.Codstatie1" class="form-control" />
    <span asp-validation-for="@Model.TaBarBody.Codstatie1" class="text-danger"></span>
</div>
<div>
    <input type="submit" asp-route-id="@ViewBag.TelegramaId" value="Save"/>
</div>
</form>

然后在你的 Edit post 操作中，id 将是 TaBarHeader.Id。

测试结果：

如何将主 ID 传递给详细外键？

How do I pass master id to detail foreign key?

entity-framework

asp.net-core-mvc

master-detail