異常「沒有ViewData項的類型'IEnumerable <SelectListItem>」MVC

Question

你好我所有我是新來的MVC，我無法找到以下例外的解決方案。

「沒有類型爲」IEnumerable「的ViewData項具有」部門「關鍵字。」

這裏是它

@using LearningMVCDAL 
@using LearningMVCDAL.Classes 
@model Employee 

@{ 
    ViewBag.Title = "Create"; 
} 

<h2>Create</h2> 

@using (Html.BeginForm()) 
{ 
    @Html.ValidationSummary(true) 

    <fieldset> 
     <legend>Employee</legend> 

     <div class="editor-label"> 
      @Html.LabelFor(model => model.Name) 
     </div> 
     <div class="editor-field"> 
      @Html.EditorFor(model => model.Name) 
      @Html.ValidationMessageFor(model => model.Name) 
     </div> 

     <div class="editor-label"> 
      @Html.LabelFor(model => model.Gender) 
     </div> 
     <div class="editor-field"> 
      @Html.DropDownList("Gender", new List<SelectListItem>{ 
     new SelectListItem { Text="Male", Value="Male"}, 
     new SelectListItem { Text="Female", Value="Female"}},"Select Gender") 
      @Html.ValidationMessageFor(model => model.Gender) 
     </div> 

     <div class="editor-label"> 
      @Html.LabelFor(model => model.City) 
     </div> 
     <div class="editor-field"> 
      @Html.EditorFor(model => model.City) 
      @Html.ValidationMessageFor(model => model.City) 
     </div> 
     <div class="editor-label"> 
      @Html.Label("Department") 
     </div> 
     <div class="editor-field"> 
      @Html.DropDownList("Department", (IEnumerable<SelectListItem>)ViewBag.Departments,"Select Department") 
     </div> 
     <p> 
      <input type="submit" value="Create" /> 
     </p> 
    </fieldset> 
} 

<div> 
    @Html.ActionLink("Back to List", "Index") 
</div> 

控制器代碼

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.Mvc; 
using LearningMVCBLL; 
using LearningMVCDAL; 
using LearningMVCDAL.Classes; 

namespace LearningMVC.Controllers 
{ 
    public class EmployeeController : Controller 
    { 

     #region ObjectDeclartions 
     EmployeeBusinessLayer objEmployeeBusinessLayer = new EmployeeBusinessLayer(); 
     DepartmentBusinessLayer objDepartmentBusinessLayer = new DepartmentBusinessLayer(); 
     #endregion 
     public ActionResult Index() 
     { 
      List<Employee> employees = objEmployeeBusinessLayer.Employee; 
      return View(employees); 
     } 
     [HttpGet] 
     public ActionResult Create() 
     { 
      List<Department> departments = new List<Department>(); 
      departments = objDepartmentBusinessLayer.Department; 
      SelectList departmentList = new SelectList(departments, "ID", "Name"); 
      ViewBag.Departments = departmentList; 
      return View(); 
     } 
     [HttpPost] 
     public ActionResult Create(FormCollection formCollection) 
     { 
      if (ModelState.IsValid) 
      { 
       foreach (string key in formCollection.AllKeys) 
       { 
        Response.Write("Key = " + key + " "); 
        Response.Write("Value = " + formCollection[key]); 
        Response.Write("<br/>"); 
       } 
      } 
      return View(); 
     } 
    } 
} 

我改變，但仍然得到了同樣的錯誤CSHTML代碼。我在發佈數據「HttpPost」創建函數時發生此錯誤。 在此先感謝。

Answer 1

嘗試添加ViewBag.Departments在創建它是使用郵政列舉HTTPMethod動作，象下面這樣：

[HttpPost] 
     public ActionResult Create(FormCollection formCollection) 
     { 
      if (ModelState.IsValid) 
      { 
       foreach (string key in formCollection.AllKeys) 
       { 
        Response.Write("Key = " + key + " "); 
        Response.Write("Value = " + formCollection[key]); 
        Response.Write("<br/>"); 
       } 
      } 
     List<Department> departments = new List<Department>(); 
     departments = objDepartmentBusinessLayer.Department; 
     SelectList departmentList = new SelectList(departments, "ID", "Name"); 
     ViewBag.Departments = departmentList; 
      return View(); 
     }