asp.net-mvc - 在 ASP.NET MVC 中的 Html.ListBox 中需要帮助

Question

我目前正在开发一个应用程序，在该应用程序中，我在 View 的列表框中显示项目列表，然后将选定的项目发送回 Controller 。

我的模型如下:

public class Items    {        [DisplayName("Items")]        public string[] Items { get; set; }    }

当用户第一次请求页面时，必须从数据库中查询项目列表并将其发送到 View 。我能够弄清楚如何在 Controller 端将项目收集到 ArrayList/string[] 中，但无法理解将 View 与模型绑定(bind)并使用 Html.ListboxFor 显示列表并将模型发回的语法表单提交。

谁能帮帮我。

谢谢。

Answer 1

查看模型:

public class MyViewModel
{
    [DisplayName("Items")]
    public string[] SelectedItemIds { get; set; }
    public IEnumerable<SelectListItem> Items { get; set; }
}

Controller :

public class HomeController : Controller
{
    public ActionResult Index()
    {
        var model = new MyViewModel
        {
            // preselect some items
            // leave empty if you want none to be selected initially
            SelectedItemIds = new[] { "1", "3" },

            // Normally you would fetch those from your database
            // hardcoded here for the purpose of the post             
            Items = Enumerable.Range(1, 10).Select(x => new SelectListItem
            {
                Value = x.ToString(),
                Text = " item " + x
            })
        };
        return View(model);
    }

    [HttpPost]
    public ActionResult Index(string[] selectedItemIds)
    {
        // here you will get the list of selected item ids
        // where you could process them
        // If you need to redisplay the same view make sure that 
        // you refetch the model items once again from the database
        ...

    }
}

查看( Razor ):

@model AppName.Models.MyViewModel
@using (Html.BeginForm())
{
    @Html.LabelFor(x => x.SelectedItemIds)

    @Html.ListBoxFor(
        x => x.SelectedItemIds, 
        new SelectList(Model.Items, "Value", "Text")
    )
    <input type="submit" value="OK" />
}

查看(WebForms):

<% using (Html.BeginForm()) { %>
    <%= Html.LabelFor(x => x.SelectedItemIds) %>

    <%= Html.ListBoxFor(
        x => x.SelectedItemIds, 
        new SelectList(Model.Items, "Value", "Text")
    ) %>
    <input type="submit" value="OK" />
<% } %>