Question

我能够从一个控制器编辑多个记录，但是在视图中编辑多个记录时，我无法成功添加DropDownList。

控制器：

public ActionResult ReportByNumber() 
{
    ViewBag.Department = new SelectList(from r in db.Departments select r, "Name", "Name");
    return View(reportList.ToList());
}

查看允许多条记录：

@for (int i = 0; i < Model.Count; i++) { 

@Html.TextBoxFor(m => m[i].Department, new { @style = "width:120px" })

}

有没有办法让Department成为DropDownList？

Answer 1

试试这个：首先在你的控制器

public ActionResult ReportByNumber() 
{
ViewBag.DepartmentID = new SelectList(from r in db.Departments select r, "DepartmentID", "Name",selectedDepartment);
return View();
}

您认为的第二个

@Html.DropDownList("DepartmentID", null, htmlAttributes: new { @class = "form-control" })

<强>＃UPDATE1 这是如何绑定您的下拉列表 值

 [HttpPost]
    public ActionResult ReportByNumber([Bind(Include = "DepartmentID")]Departments dept)
    {
    //......
    }

Answer 2

在集合中使用@Html.DropDownList()时，您需要使用编辑器模板（或在每次迭代中重建SelectList，这不是非常有效）。假设你的模型是

public class ReportModel
{
  [Required(ErrorMessage = "Please select a department")]
  public string Department { get; set; }
  ....
}

然后在控制器中

public ActionResult ReportByNumber() 
{
  var departments = (from r in db.Departments select r).ToList();
  ViewBag.DepartmentList = new SelectList(departments, "Name", "Name");
  return View(reportList.ToList());
}

EditorTemplate（/Views/Shared/EditorTemplates/ReportModel.cshtml）

@model ReportModel
....
@Html.LabelFor(m => m.Department)
@Html.DropDownListFor(m => m.Department, (SelectList)ViewData["DepartmentList"], "-Please select-")
@Html.ValidationMessageFor(m => m.Department)
....

主视图

@model List<ReportModel>
@using(Html.BeginForm())
{
  @Html.EditorFor(m => m, new { DepartmentList= ViewBag.DepartmentList})
  <input type="submit" />
}

注意：EditorTemplate的名称必须与模型名称匹配。您的代码建议您只想绑定到Name的{{1}}属性（不是ID属性），在这种情况下它可以只是

Department

Answer 3

谢谢Stephen和Feras让我走上正轨。

我最终在视图中使用了以下代码：

@Html.DropDownListFor(m => m[i].Department, (IEnumerable<SelectListItem>)ViewBag.Department, item.Department ?? "")

使用DropDownList在视图中编辑多个记录

3 个答案: