MVC 2：如何使用 Html.DropDownListFor？

Question

我还不确定我的 lambda，但为什么以下内容不起作用？ 4/mvc2

作品：

// SpotlightsController.cs
public class SpotlightFormViewModel
{

    // props
    public Spotlight Spotlight { get; private set; }
    public SelectList Featured { get; private set; }
    public IDictionary<string, int> feature = new Dictionary<string, int>(){
        {"True", 1},
        {"False", 0},
    };

    // constr
    public SpotlightFormViewModel(Spotlight spotlight)
    {
        Spotlight = spotlight;
        Featured = new SelectList(feature.Keys, spotlight.Featured);
    }
}

// Edit.aspx
<div class="editor-label">
    <label for="Featured">Featured:</label>
</div>
<div class="editor-field">
    <%: Html.DropDownList("Featured", Model.Featured)%>
    <%: Html.ValidationMessage("Featured") %>
</div>

不起作用：

// Compiler Error Message: CS1501: No overload for method 'DropDownListFor' takes 1 arguments
// Edit.aspx
<div class="editor-label">
    <%: Html.LabelFor(model => model.Featured) %>
</div>
<div class="editor-field">
    <%: Html.DropDownListFor(model => model.Featured)%>
    <%: Html.ValidationMessageFor(model => model.Featured) %>
</div>

Answer 1

DropDownListFor 接受（至少）两个参数。第一个参数是将在回发时保存所选值的属性（并包含当前所选值），第二个参数是IEnumerable<SelectListItem>，其中包含选项的键/值对。将您的 Feature 属性重命名为 FeatureMenu 或其他名称，并创建与选项值对应的类型的属性名称 Featured。然后将 FeatureMenu 添加到 DropDownListFor 的参数中。

 public SelectList FeatureMenu { get; private set; }
 public string Featured { get; private set; }

...

 <%: Html.DropDownListFor( model => model.Featured, Model.FeatureMenu ) %>