ASP.Net MVC2 DropDownListFor [英] ASP.Net MVC2 DropDownListFor

问题描述

我想学MVC2，C＃和LINQ到实体都在同一个项目（是的，我是疯了），我遇到了一些问题，DropDownListFor和传球选择列表吧。

I am trying to learn MVC2, C# and Linq to Entities all in one project (yes, I am mad) and I am experiencing some problems with DropDownListFor and passing the SelectList to it.

这是在我的控制器中的code：

This is the code in my controller:

public ActionResult Create()
{
    var Methods = te.Methods.Select(a => a);

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

    foreach (Method me in Methods)
    { 
        SelectListItem sli=new SelectListItem();
        sli.Text = me.Description;
        sli.Value = me.method_id.ToString();
        MethodList.Add(sli);
    }

    ViewData["MethodList"] = MethodList.AsEnumerable();

    Talkback tb = new Talkback();
    return View(tb);
} 

和我有麻烦试图让 DropDownListFor 取 methodList时在 ViewData的。当我尝试：

and I am having troubles trying to get the DropDownListFor to take the MethodList in ViewData. When I try:

<%:Html.DropDownListFor(model => model.method_id,new SelectList("MethodList","method_id","Description",Model.method_id)) %>

它的错误了以下消息

It errors out with the following message

DataBinding: 'System.Char' does not contain a property with the name 'method_id'.

我知道这是为什么，因为它正在 methodList时作为一个字符串，但我无法弄清楚如何得到它采取的SelectList 。如果我在一个正常的以下的DropDownList ：

I know why this is, as it is taking MethodList as a string, but I can't figure out how to get it to take the SelectList. If I do the following with a normal DropDownList:

<%: Html.DropDownList("MethodList") %>

有与此非常高兴。

谁能帮助？

推荐答案

修改：那么您使用的是实体框架，是吗？在你把注释中的另外信息的话，你会想要做这样的事情：

EDIT: So you are using Entity Framework, yes? In that case with the addition info you put in the comments, you would want to do something like this:

public ActionResult Create()
{
    var viewModel = new CreateViewModel(); // Strongly Typed View

    using(Entities dataModel = new Entities()) // 'te' I assume is your data model
    {
         viewModel.Methods = dataModel.Methods.Select(x => new SelectListItem()
         {
              Text = x.Description,
              Value = x.method_id.ToString()
         });
    }

    return View(viewModel);
}

您强类型的视图模型将是：

Your strongly typed view model would be:

public class CreateViewModel
{
     public string SelectedMethod { get; set; }
     public IEnumerable<SelectListItem> Methods { get; set; }
}

您认为code将是：

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<CreateViewModel>" %>
 <%-- Note the Generic Type Argument to View Page! --%>
 <%: Html.DropDownListFor(m => m.SelectedMethod, Model.Methods) %>

这篇关于ASP.Net MVC2 DropDownListFor的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！