Question

所以我创建了一个下拉列表，我根据列表中的选定值更改了语言，但是当它提交时我松开了所选的值并重置了。有什么方法可以记住我提交时所选择的内容吗？

@using (Html.BeginForm("SetCulture", "Home", new { @onsubmit = @"$(#Languages option:selected).text();" }))
@Html.DropDownList("Languages", Test.Configuration.GetLanguages().Select(x => new SelectListItem() { Text = x.Text, Value = x.Value }), new{@onchange = @"$(form).submit();"})

Answer 1

您应该使用语法

@Html.DropDownListFor(model => model.Language, new SelectList(Test.Configuration.GetLanguages().Select(x => new SelectListItem() { Text = x.Text, Value = x.Value })))

然后MVC知道使用该字段存储下拉列表中的所选选项。

根据下面的评论，这就是我在模型中声明语言的方式：

PageViewModel.cs

public class PageViewModel {
    ...
    public string Language { get; set; }
    public SelectList Languages { get; set; }
}

HomeController.cs

    public ActionResult Index(PageViewModel pageViewModel)
    {
        //put breakpoint on the return view and after you submit a selection you'll see that the pageViewModel argument has the language of what you selected
        return View(new PageViewModel
            {
                Language = "English",
                Languages = new SelectList(new List<string>
                {
                    "English",
                    "Danish",
                    "Spanish",
                    "French"
                })
            });
    }

Index.cshtml

@model MvcPlayground.Controllers.PageViewModel
<h2>Languages!</h2>

@using (Html.BeginForm())
{
    @Html.DropDownListFor(model => model.Language, Model.Languages)
    <input type="submit"/>
}

MVC将使用language属性来确定回发中的所选项目，只要您正确传递它。

Answer 2

您可以像这样更改代码

  public ActionResult Index()
    {
        //pass the Enumerable<SelectListItem>  in to viewbag
       ViewBag.Countrys = new List<SelectListItem>{
                new SelectListItem { Selected = true, Text = "-Select-", Value = "-1"},
                 new SelectListItem {  Text = "India", Value = "100"},
                  new SelectListItem {  Text = "US", Value = "101"},

            };


        return View();
    }

你需要一个像这样的模型

 public class HomeModel
{
    public string FirstName { get; set; }

    public int CountryId { get; set; }
}

然后在视图中

     @model Stratergy.Models.Home.HomeModel

@using (@Html.BeginForm("YourAction", "your controller"))
{
    <fieldset>
     <legend>Personal Form:</legend>

    @Html.TextBoxFor(model=>model.FirstName)
    @Html.DropDownListFor(model=>model.CountryId,(IEnumerable<SelectListItem>)@ViewBag.Countrys)

    <input type="submit" value="Finish" />
    </fieldset>
}

当formpost

时，您可以在模型中获取所选值

    [HttpPost]
    public ActionResult YourAction(HomeModel homeModel)
    {

        return Json(new { Result = "OK"});
    }

MVC html.dropdownlist伪造选定的值？

2 个答案: