ASP.NET MVC5 - Problem with DropDownListFor.

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C#

ASP.NET

MVC

MVC5

Hello,

I changed my model class (Document), and i inserted one dropdownlist to my Playlist propertie. But, the Bind method of my object dont working fine for this situation.

the problem is: my Playlist propertie value comes NULL into Create method.

Document Model:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Data.Entity;
using System.Linq;
using System.Web;

namespace Desenvolvimento.Models
{
    public enum DocumentCategory
    {
        Photo = 0,
        Music = 1,
        Video = 2,
        Other = 3
    }

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

        [Required]
        [Display(Name = "Nome")]
        public string Name { get; set; }

        [Display(Name = "Descrição")]
        public string Description { get; set; }

        //[Required]
        public string Path { get; set; }

        [Required]
        [Display(Name = "Categoria")]
        public DocumentCategory Category { get; set; }
        
        [Display(Name="Privado")]
        public bool isPrivate { get; set; }

        [Display(Name = "Playlist")]
        public virtual Playlist Playlist { get; set; }
        
        //[Required]
        public virtual MyUser User { get; set; }
    }
    
}

Document Create View:

@model Desenvolvimento.Models.Document

@{
    ViewBag.Title = "Create";
    Layout = "~/Views/Shared/_Layout.cshtml";       
}

<h2>Create</h2>


@using (Html.BeginForm("Create", "Document", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    @Html.AntiForgeryToken()
    
    <div class="form-horizontal">
        <h4>Document</h4>
        <hr />
        @Html.ValidationSummary(true)

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

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

        <div class="form-group">
            <label class="control-label col-md-2">Selecione o arquivo:</label>
            @*@Html.LabelFor(model => model.Path, new { @class = "control-label col-md-2" })*@
            <div class="col-md-10">
                @*@Html.EditorFor(model => model.Path)
                @Html.ValidationMessageFor(model => model.Path)*@
                <input type="file" name="upload" class="btn btn-default" />

            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Category, new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @{
                    List<SelectListItem> listItems = new List<SelectListItem>();
                    listItems.Add(new SelectListItem
                         {
                             Text = "Fotos",
                             Value = "Photo"
                         });
                    listItems.Add(new SelectListItem
                         {
                             Text = "Vídeos",
                             Value = "Video"
                         });
                    listItems.Add(new SelectListItem
                         {
                             Text = "Músicas",
                             Value = "Music"
                         });
                    listItems.Add(new SelectListItem
                        {
                            Text = "Outros",
                            Value = "Other"
                        });
                }

                @Html.DropDownListFor(model => model.Category, listItems, "-- Selecione a Categoria --", new { @class = "select" })
                @Html.ValidationMessageFor(model => model.Category)
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Playlist, new { @class = "control-label col-md-2" })
            <div class="col-md-10">               
                @Html.DropDownListFor(model => model.Playlist, ((Desenvolvimento.Controllers.DocumentController)this.ViewContext.Controller).GetPlaylists(), "-- Selecione a Playlist --", new { @class = "select" })  
                @Html.ValidationMessageFor(model => model.Playlist)              
            </div>
        </div>

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

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

Document Controller:

//return dropdownlist
 public List<SelectListItem> GetPlaylists()
        {
            List<SelectListItem> playlists = new List<SelectListItem>();

            try
            {
                playlists.Add(new SelectListItem { Text = "-- Selecione a Playlist --", Value = "0" });
                foreach (var item in db.Playlists)
                {
                    playlists.Add(new SelectListItem { Text = item.Name, Value = Convert.ToString(item.Id) });
                }
            }
            catch (Exception)
            {                
                throw;
            }

            return playlists;            
        }


 [HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<ActionResult> Create([Bind(Include = "Id,Name,Description,Path,Category,isPrivate,Playlist,Album")] Document document)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    
                    db.Documents.Add(document);
                    await db.SaveChangesAsync();
                }
                catch (Exception)
                {
                    throw;
                }

                return RedirectToAction("Index");
            }


           return View(document);
        }