ViewData（MVC）遇到一些困难

Question

我正在为学校做一个MVC5项目，我正在使用一个关于项目和任务的模型。基本上，您可以创建，编辑，更新和删除项目（CRUD），但是，对于每个项目，您可以拥有不同的任务。所以Project和Task模型是这样的：

 [Table("Projectos")]
    public class ProjectoModel
    {
        [Key]
        public int ProjectoID { get; set; } //ProjectID
        [Required]
        [Display(Name="Nome")]
        public string ProjectoNome { get; set; } //ProjectName
        [Required]
        [Display(Name="Descrição")]
        public string ProjectoDescricao { get; set; } //ProjectoDescription
        [Display(Name="Equipa Responsável")]
        public int EquipaResponsavelID { get; set; }
        public virtual EquipaModel EquipaResponsavel { get; set; } // ResponsibleTeam
         [Display(Name = "Concluído")]
        public bool ProjectoConcluido { get; set; } //ProjectOver
    }

[Table("Tarefa")]
     public class TarefaModel
            {
                [Key]
                public int TarefaID { get; set; } //TaskID
                [Required]
                [Display(Name = "Nome")]
                public string TarefaNome { get; set; } //TaskName
                [Required]
                [Display(Name = "Descrição")]
                public string TarefaDescricao { get; set; } //TaskDetails
                [Required]
                [Display(Name = "Concluída")]
                public bool TarefaConcluida { get; set; } //TaskDone
                [ForeignKey("Projecto")]
                public int ProjectoAssociadoID { get; set; }
                public virtual ProjectoModel Projecto { get; set; } //AssociatedProject

            }

然后我有ProjectController，其中包含与任务相关的操作，因为每组任务都属于一个Project

// GET: Projectos/Tarefas/5
public ActionResult Tarefas(int id)
{
    var tarefas = db.Tarefas.Where(tarefa => tarefa.ProjectoAssociadoID == id).ToList();
    TempData["IDProjecto"]=id;
    return View(tarefas);
}

// GET: Projectos/Tarefas/Create
public ActionResult CreateTarefas(int id) {
    TempData["IDProjecto"] = id;
    return View();
}

// POST
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult CreateTarefas([Bind(Include = "TarefaID,TarefaNome,TarefaDescricao")] TarefaModel tarefaModel)
{
    if (ModelState.IsValid)
    {
        if (TempData["IDProjecto"] != null)
        {
            tarefaModel.ProjectoAssociadoID = Convert.ToInt32((TempData["IDProjecto"]).ToString());
            db.Tarefas.Add(tarefaModel);
            db.SaveChanges();
            return RedirectToAction("Index");
        }
    }

    return View(tarefaModel);
}

所以传递ProjectID直到创建任务我在控制器和视图之间使用TempData。

例如在Tarefas View中： @ Html.ActionLink（“Criar Tarefa”，“CreateTarefas”，新{id = TempData [“IDProjecto”]}）

但是，对于CreateTarefas View，由于我正在使用提交操作，因此我无法将TempData从View传递到POST操作。正如你在上面看到的，我检查TempData是否为空，它确实是，我检查它。我希望获得TempData，因此每次创建Task时，ProjectID都会自动与任务相关联。我不知道自己是否解释得很好，谢谢你的帮助。 ;）

（PS：我的CreateTarefas视图）

@model CodingsESW.Models.TarefaModel

@{
    ViewBag.Title = "Criar Tarefa";
}

<h2>Criar Tarefa</h2>


@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>Criar uma Tarefa</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.TarefaNome, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.TarefaNome, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.TarefaNome, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.TarefaDescricao, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.TarefaDescricao, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.TarefaDescricao, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </div>
    </div>
}

<div>
    @Html.ActionLink("Back to List", "Tarefas", new { id = TempData["IDProjecto"] })
</div>

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}