MVC ViewModel没有发回

Question

我正在使用Viewmodel，但是当我提交表单时，我没有收到值。

我有一个像这样的模型......

Public Class ProductSummaryModel

    Property productGUID As Integer
    Property productName As String
    Property productPrice As Double
    Property productSku As String
    Property categories As String()
    Property ShipsWithin As Nullable(Of Integer)
    <AllowHtml>
    Property productWebDescription As String
    Property ImageMainPath As String

End Class

然后我有一个像这样的ViewModel ......

Public Class ProductViewModel
    Public ProductSummary As ProductSummaryModel
End Class

这是我的控制器...

Public Function Add() As ActionResult ' Default View To Add  Item
    Dim prdsummary As ProductViewModel = New ProductViewModel
    Return View("Add", prdsummary)
End Function

在我的＆＃34;添加＆＃34;查看我有以下内容......

<tr>
    <td>Price: </td>
    <td><%=Html.TextBoxFor(Function(f) f.ProductSummary.productPrice)%></td>
</tr>

问题是，当我提交FORM时，我无法获得POSTED表单值。

    Public Function AddItem(ByVal Model As ProductViewModel) As ActionResult ' Add Item into DB

        Dim ajaxMessage As New AjaxFormResponse

        Dim prd As ProductSummaryModel = New ProductSummaryModel
        Model.ProductSummary = prd

        Dim skuID As Integer = 0
        msgbox(Model.ProductSummary.categories) ' Empty

End Function

可能有更好的方法来解决这个问题。

*更新 * *

我已经弄明白问题是什么......当将Model传递给ViewModel时，我必须这样做......

Dim Product As ProductViewModel = New ProductViewModel
Dim ProductSummary As New ProductSummaryModel
Product.ProductSummary = ProductSummary
Return View("Add", Product)

Answer 1

为什么不使用ProductSummaryModel进行绑定而不是ProductViewModel。这样你就可以保持简单。如果可以，请避免使用嵌套绑定。 另外请确保您在视图中使用如下，以及HttpPost attr。在控制器中

产品控制器

Public Class ProductController
Inherits Controller

' Main Action
Public Function Main() As ActionResult 
    Dim prdViewModel As ProductViewModel = New ProductViewModel       
    prdViewModel.ProductSummary = New ProductSummaryModel
    Return View("Main", prdViewModel)
End Function

' Partial Action
Public Function Add() As ActionResult 
    Dim prdViewModel As ProductViewModel = New ProductViewModel
    prdViewModel.ProductSummary = New ProductSummaryModel

    Return View("Add", prdViewModel)
End Function

'POST Action from Partial View
<HttpPost()> _
 Public Function AddItem(ByVal Model As ProductSummaryModel) As ActionResult ' Add Item into DB
   msgbox(Model.productPrice) ' Empty
End Function

End Class

主视图

<%@ Page Title="" Language="VB" MasterPageFile="~/Views/Shared/Site.Master" 
    Inherits="System.Web.Mvc.ViewPage(Of MvcApplication2.ProductViewModel)" %>

<asp:Content ID="manageTitle" ContentPlaceHolderID="TitleContent" runat="server">
    Main Page
</asp:Content>

<asp:Content ID="manageContent" ContentPlaceHolderID="MainContent" runat="server">
    <%
        Html.RenderPartial("_Add", Model.ProductSummary)
     %>
</asp:Content>

部分视图

    <%@ Page Language="VB" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage(Of MvcApplication2.ProductSummaryModel)" %>

<asp:Content ID="registerTitle" ContentPlaceHolderID="TitleContent" runat="server">
    Register
</asp:Content>

<asp:Content ID="registerContent" ContentPlaceHolderID="MainContent" runat="server">

    <% Using Html.BeginForm("AddItem", "Product")%>
        <%: Html.AntiForgeryToken() %>
        <tr>
            <td>Price: </td>
            <td><%: Html.TextBoxFor(Function(f) f.productPrice) %></td>
        </tr>
        <input type="submit" value="Register" />
    <% End Using%>
</asp:Content>

更新视图模型

 Public Class ProductSummaryModel

    Property productGUID As Integer
    Property productName As String
    Property productPrice As Double
    Property productSku As String
    Property categories As String()
    Property ShipsWithin As Nullable(Of Integer)
    <AllowHtml>
    Property productWebDescription As String
    Property ImageMainPath As String

End Class

Public Class ProductViewModel
    Public ProductSummary As ProductSummaryModel
End Class

Answer 2

我看到两个问题：

首先，当您执行此操作时，您将覆盖已过帐的值：

Dim prd As ProductSummaryModel = New ProductSummaryModel
Model.ProductSummary = prd

来自视图的模型中的ProductSummary属性将丢失，并且只有在读取其属性时才会获得默认值。

此外，您不会在视图中显示如何设置categories值。您是否允许此属性的用户输入或其他操作？