asp.net-mvc - VB.NET - 使用 ListBoxFor 和 DropDownList

Question

我对这个 ASP.net MVC 的东西很陌生，并且真的被困在 ListBoxFor 和 DropDownListFor 上。

我该如何使用它们？有什么例子吗？

Answer 1

这真的没那么难。与往常一样，您从定义视图模型开始：

Public Class MyViewModel
    Public Property SelectedItems As IEnumerable(Of String)
    Public Property SelectedItem As String
    Public Property Items As IEnumerable(Of SelectListItem)
End Class

然后是控制器：

Public Class HomeController
    Inherits System.Web.Mvc.Controller

    Function Index() As ActionResult
        Dim model = New MyViewModel With {
            .Items = {
                New SelectListItem() With {.Value = "1", .Text = "item 1"},
                New SelectListItem() With {.Value = "2", .Text = "item 2"},
                New SelectListItem() With {.Value = "3", .Text = "item 3"}
            }
        }
        Return View(model)
    End Function

    Function Index(model As MyViewModel) As ActionResult
        ' Here you can use the model.SelectedItem which will
        ' return you the id of the selected item from the DropDown and 
        ' model.SelectedItems which will return you the list of ids of
        ' the selected items in the ListBox.
        ...
    End Function
End Class

最后是相应的强类型视图：

@ModelType MvcApplication1.MyViewModel

@Using Html.BeginForm()
    @Html.DropDownListFor(Function(x) x.SelectedItem, Model.Items)
    @Html.ListBoxFor(Function(x) x.SelectedItems, Model.Items)
    @<input type="submit" value="OK" />
End Using