MVC5中數據庫中的下拉列表

Question

ViewModel：

public class GroepModel
    {
        public int id { get; set; }
        public String Naam { get; set; }
        public String Beschrijving { get; set; }
    }

控制器：

public class GroepController : Controller
{
    AlinaDatabaseDataContext db = new AlinaDatabaseDataContext();
    // GET: Groep
    public ActionResult Groepen()
    {
        List<GroepModel> groepen = Mapper.Map<List<GroepenWerkvorm>, List<GroepModel>>(db.GroepenWerkvorms.ToList());

        return View(groepen);
    }
}

視圖

@model alina1617.Models.GroepModel

@{
    ViewBag.Title = "Groepen";
}

<h2>Groepen</h2>
<div>
    @Html.DropDownListFor(model => model. //This is not working  )
</div>

我環顧四周，發現很多東西可以使用ViewBags解決，但使用它們不是次優的嗎？ 那么，使用具有數據庫數據的模型類來獲取下拉列表的最佳方法是什么？

Answer 1

首先，您需要向ViewModel中添加一個SelectList：

public class MyViewModel {
   public SelectList list {get;set;}
   public int selectedItem {get;set;}
}

那么您需要將列表添加到SelectList中：

public class GroepController : Controller
{
    AlinaDatabaseDataContext db = new AlinaDatabaseDataContext();
    // GET: Groep
    public ActionResult Groepen()
    {
        List<GroepModel> groepen = Mapper.Map<List<GroepenWerkvorm>,     List<GroepModel>>(db.GroepenWerkvorms.ToList());

        var model = new MyViewModel();

        model.list = new SelectList(groepen, "id", "Naam");

        return View(model);
    }
}

並在視圖中：

@model alina1617.Models.MyViewModel

@{
    ViewBag.Title = "Groepen";
}

<h2>Groepen</h2>
<div>
    @Html.DropDownListFor(model => model.selectedItem, Model.list  )
</div>