Question

Controller

public class ProController : Controller
    {
        string CS = ConfigurationManager.ConnectionStrings["OnlineInventoryDB"].ConnectionString;

        [HttpGet]
        public ActionResult Create()
        {
            Get_catagory();
            return View();
        }

        [HttpPost]
        [ActionName("Create")]
        public ActionResult Create_Post(Product product)
        {


            if (ModelState.IsValid)
            {
                pro.AddProduct(product);
                return RedirectToAction("Index");
            }
            return View();
        }



        public void Get_catagory()
        {

            SqlConnection con = new SqlConnection(CS);
            if (con.State == ConnectionState.Closed)
            {
                con.Open();
            }
            SqlDataAdapter sda = new SqlDataAdapter("DDLCatagory", con);
            sda.SelectCommand.CommandType = CommandType.StoredProcedure;
            DataTable dt = new DataTable();
            sda.Fill(dt);

            List<SelectListItem> ddlcatlist = new List<SelectListItem>();

            foreach(DataRow dr in dt.Rows)
            {
                ddlcatlist.Add(new SelectListItem { Text = dr["Catagory"].ToString(), Value = dr["Cat_ID"].ToString() });
            }
            ViewData["cataglistddl"] = ddlcatlist;
        }


    }

强烈打字

@model BuisnessLogics.Product

@{
    ViewBag.Title = "Create";
}

<h2>Create</h2>

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

    <div class="form-horizontal">
        <h4>Product</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Prod_Catagory, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.DropDownList("ddlcataglist", ViewData["cataglistddl"] as List<SelectListItem>,"Select Cataegory", new { @class = "form-control" })
                @Html.ValidationMessageFor(model => model.Prod_Catagory, "", new { @class = "text-danger" })
            </div>
        </div>

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

在页面提交时，没有显示“IEnumerable”类型的ViewData项，其中显示了“ddlcataglist”键，并且未提交页面。

Answer 1

您还需要在post方法中重新绑定您的下拉列表。

[HttpPost]
[ActionName("Create")]
 public ActionResult Create_Post(Product product)
 {
      Get_catagory();
      if (ModelState.IsValid)
      {
          pro.AddProduct(product);
          return RedirectToAction("Index");
      }

    return View();
 }

没有类型为'IEnumerable <selectlistitem>'的ViewData项具有键'ddlcataglist'

1 个答案: