c# - 附加信息: There is no ViewData item of type 'IEnumerable Asp.NET MVC

Question

我遇到了问题
请帮我
错误:其他信息:没有类型为“IEnumerable”的ViewData项，其键为“

MyAction代码

 [HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult GiderEkle(Faturalar fatura, Giderler gideriki)
    {
        List<SelectListItem> item8 = new List<SelectListItem>();
        foreach (var c in db.Caris)
        {
            item8.Add(new SelectListItem
            {
                Text = c.Adi,
                Value = c.CariID.ToString()
            });

        }

        ViewBag.countrydrop = item8;

        return View();
    }

我的.cshtml代码

<div class="form-group">
        <p>Müşterı Adı</p>
        <div class="col-md-10">
            @Html.DropDownList("country",(IEnumerable<SelectListItem>)ViewBag.country,"Select country")
            @Html.ValidationMessageFor(model => model.CariID, "", new { @class = "text-danger" })
        </div>
    </div>

我的模特Cari，

public class Cari
{
    [Key]
    public int CariID { get; set; }
    public IEnumerable<SelectListItem> DropDownItems { get; set; }
    public bool MusteriTip { get; set; }
    public string Unvan { get; set; }
    public string TC { get; set; }
    public string Adi { get; set; }
    public string Soyadi { get; set; }
    public string Adres { get; set; }
    public string VD { get; set; }
    public string VKN { get; set; }
    public string Telefon { get; set; }
    public string Email { get; set; }
    public string WebSite { get; set; }
}

Faturalar模型，

public class Faturalar
{
    [Key]
    public int FaturaID { get; set; }
    public string Tarih { get; set; }
    public int CariID { get; set; }
    [ForeignKey("CariID")]
    public Cari Caris { get; set; }
    public int FaturaNo { get; set; }
    public List<Giderler> Giderlers { get; set; }
}

吉德勒模型

 public class Giderler
{
    [Key]
    public int GiderlerID { get; set; }
    public int FaturaID { get; set; }
    [ForeignKey("FaturaID")]
    public Faturalar Faturalar { get; set; }
    public string Aciklama { get; set; }
    public int Miktar { get; set; }
    public string Birim { get; set; }
    public double Fiyat { get; set; }
    public double KDV { get; set; }
    public double Tutar { get; set; }
}

最后是好的一面

@model UmtKontrolMerkezi.Models.Faturalar

Answer 1

ViewBag属性称为countrydrop，您正尝试将ViewBag.country转换为不存在的IEnumerable<SelectListItem>。

您可以使用:

@Html.DropDownList("country",(IEnumerable<SelectListItem>)ViewBag.countrydrop,"Select country")

这将引用您在GiderEkle Action Method中定义的正确变量，但是与 ViewBag方法相比，我更喜欢强类型 View 模型。

我已经通过以下 fiddle 证明了这一工作:

https://dotnetfiddle.net/xXnQwy

操作方法:

    public ActionResult DropDownListTest()
    {
        var myList = new List<SelectListItem>();

        myList.Add(new SelectListItem { Text = "Darren one", Value = "1" });
        myList.Add(new SelectListItem { Text = "Darren two", Value = "2" });
        myList.Add(new SelectListItem { Text = "Darren three", Value = "3" });

        ViewBag.DarrenList = myList;

        return View();
    }

CSHTML文件:

@Html.DropDownList("DarrenId",(IEnumerable<SelectListItem>)ViewBag.DarrenList)