ASP.NET Web窗体4.5模式的结合，其中模型包含集合 [英] ASP.NET Web Forms 4.5 model binding where the model contains a collection

问题描述

我想更新旧的Web窗体应用程序使用的新模型绑定在4.5新增的功能，类似于MVC绑定功能。

I'm trying to update an old Web Forms application to use the new model binding features added in 4.5, similar to the MVC binding features.

我无法做一个可编辑的FormView了presents包含简单成员加上它是其他机型的集合成员的单一模式。我需要的用户能够编辑的父对象的简单属性和子集的属性。

I'm having trouble making an editable FormView that presents a single model that contains simple members plus a member that is a collection of other models. I need the user to be able to edit the simple properties of the parent object and the properties of the child collection.

问题是，孩子集合（ ProductChoice.Extras ）总是经过模型绑定时，code试图更新模型空。

The problem is that the child collection (ProductChoice.Extras) is always null after model binding when the code is trying to update the model.

下面是我的模型：

[Serializable]
public class ProductChoice
{
    public ProductChoice()
    {
        Extras = new List<ProductChoiceExtra>();
    }

    public int Quantity { get; set; }
    public int ProductId { get; set; }
    public List<ProductChoiceExtra> Extras { get; set; }
}

[Serializable]
public class ProductChoiceExtra
{
    public int ExtraProductId { get; set; }
    public string ExtraName { get; set; }
    public int ExtraQuantity { get; set; }
}

和后面我的用户控制code：

And my user control code behind:

public partial class ProductDetails : System.Web.UI.UserControl
{
    private Models.ProductChoice _productChoice;

    protected void Page_Load(object sender, EventArgs e)
    {
        _productChoice = new Models.ProductChoice()
        {
            Quantity = 1,
            ProductId = 1
        };
        _productChoice.Extras.Add(new Models.ProductChoiceExtra()
        {
            ExtraProductId = 101,
            ExtraName = "coke",
            ExtraQuantity = 1
        });
        _productChoice.Extras.Add(new Models.ProductChoiceExtra()
        {
            ExtraProductId = 104,
            ExtraName = "sprite",
            ExtraQuantity = 2
        });

    }

    public Models.ProductChoice GetProduct()
    {
        return _productChoice;
    }

    public void UpdateProduct(Models.ProductChoice model)
    {
        /* model.Extras is always null here, it should contain two ProductChoiceExtra objects */

        if (TryUpdateModel(_productChoice) == true)
        {
        }
    }
}

我的控制标记：

<div id="selectOptions">
    <asp:FormView runat="server" ID="fvProductSelection" DefaultMode="Edit"
        ItemType="Models.ProductChoice"
        SelectMethod="GetProduct"
        UpdateMethod="UpdateProduct" >

        <EditItemTemplate>
            <asp:linkbutton id="UpdateButton" text="Update" commandname="Update" runat="server"/>
            <asp:HiddenField runat="server" ID="ProductId" Value="<%# BindItem.ProductId %>" />
            <asp:TextBox Text ="<%# BindItem.Quantity %>" ID="Quantity" runat="server" />

            <asp:Repeater ID="Extras" ItemType="Models.ProductChoiceExtra" DataSource="<%# BindItem.Extras %>" runat="server">
                <ItemTemplate>
                    <asp:HiddenField Value="<%# BindItem.ExtraProductId %>" ID="ExtraProductId" runat="server"  />
                    <asp:Label Text="<%# BindItem.ExtraName %>" ID="Name" runat="server" />
                    <asp:TextBox Text="<%# BindItem.ExtraQuantity %>" ID="Quantity"  runat="server" />
                </ItemTemplate>
            </asp:Repeater>
        </EditItemTemplate>
    </asp:FormView>
</div>

我试图使其他属性的BindingList 而非列表但它并没有任何区别，在其他集合不绑定的的UpdateProduct 方法。

I have tried making the Extras property a BindingList rather than a List but it didn't make any difference, the Extras collection isn't bound in the UpdateProduct method.

推荐答案

您应该指定直放站作为属性的项目模板的编辑项模板可能无法在自动构建的模型返回，并传递到更新方法。
我已经没有时间去尝试，但这个应该工作...

You should specify an Edit Item Template in the Repeater as the Properties in the Item Template may not be returned in the model that is constructed automatically and passed to the Update method. I've not had time to try it but this should work...

<div id="selectOptions">
    <asp:FormView runat="server" ID="fvProductSelection" DefaultMode="Edit"
        ItemType="Models.ProductChoice"
        SelectMethod="GetProduct"
        UpdateMethod="UpdateProduct" >

        <EditItemTemplate>
            <asp:linkbutton id="UpdateButton" text="Update" commandname="Update" runat="server"/>
            <asp:HiddenField runat="server" ID="ProductId" Value="<%# BindItem.ProductId %>" />
            <asp:TextBox Text ="<%# BindItem.Quantity %>" ID="Quantity" runat="server" />

            <asp:Repeater ID="Extras" ItemType="Models.ProductChoiceExtra" DataSource="<%# BindItem.Extras %>" runat="server">
                <EditItemTemplate>
                    <asp:HiddenField Value="<%# BindItem.ExtraProductId %>" ID="ExtraProductId" runat="server"  />
                    <asp:Label Text="<%# BindItem.ExtraName %>" ID="Name" runat="server" />
                    <asp:TextBox Text="<%# BindItem.ExtraQuantity %>" ID="TextBox1"  runat="server" />
                </EditItemTemplate>
                <ItemTemplate>
                    <asp:HiddenField Value="<%# BindItem.ExtraProductId %>" ID="ExtraProductId" runat="server"  />
                    <asp:Label Text="<%# BindItem.ExtraName %>" ID="Name" runat="server" />
                    <asp:TextBox Text="<%# BindItem.ExtraQuantity %>" ID="Quantity"  runat="server" />
                </ItemTemplate>
            </asp:Repeater>
        </EditItemTemplate>
    </asp:FormView>
</div>

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