Question

我的数据库中有这两个表，名为Vendors和VendorPriceBreaks：

Vendors
-----------------
VendorID (PK)
Name

VendorPriceBreaks
-----------------
VendorPriceBreakID (PK)
VendorID (FK)
Price
PaymentTypeID (FK)

我有一个视图页面可以同时添加Vendor和VendorPriceBreaks。

这是我的VendorsViewModel：

public class VendorsViewModel
{
    [HiddenInput(DisplayValue = false)]
    public int VendorId { get; set; }

    public string Name { get; set; }

    public IEnumerable<VendorPriceBreaksViewModel> VendorPriceBreaks { get; set; }
}

这是我的VendorPriceBreaksViewModel：

public class VendorPriceBreaksViewModel
{
    [HiddenInput(DisplayValue = false)]
    public int VendorPriceBreakId { get; set; }

    public double? Price { get; set; }
    public int? PaymentTypeId { get; set; }

    public IEnumerable<PaymentType> PaymentTypes { get; set; }
}

以下是供应商的视图页面：

<%: Html.TextBoxFor(m => m.Name)%>

<table id="dynamic-rows" cellpadding="0" cellspacing="0">
<% foreach (var item in Model.VendorPriceBreaks)
    Html.RenderPartial("VendorPriceBreakRow", item);
%>
</table>

这是我的控制：

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<CopyCraft.WebUI.Areas.Admin.Models.VendorPriceBreaksViewModel>" %>

<tr class="dynamic-row">
    <% using(Html.BeginCollectionItem("vendorPriceBreaks")) { %>
        <td>$<%= Html.TextBoxFor(m => m.Price) %></td>
        <td><%= Html.DropDownListFor(m => m.PaymentTypeId, new SelectList(Model.PaymentTypes, "PaymentTypeID", "Name"), "- Select a Payment Type -")%></td>
    <% } %>
</tr>

当我编辑供应商并加载价格中断时，会设置价格，但不会设置下拉列表中的PaymentType值。

以下是编辑供应商时的功能：

public ActionResult Edit(int id)
{
    var vendor = _adminRepository.GetVendor(id);

    List<VendorPriceBreaksViewModel> priceBreakssViewModels = new List<VendorPriceBreaksViewModel>();
    foreach (VendorPriceBreak priceBreak in vendor.VendorPriceBreaks)
    {
        priceBreaksViewModels.Add(new VendorPriceBreaksViewModel
            {
                Price = sheetPrice.Price,
                PaperUnitTypeId = sheetPrice.PaperUnitTypeID,
                PaperUnitTypes = _adminRepository.GetAllPaperUnitTypes()
            }
        );
    }

    var viewModel = new VendorsViewModel
    {
        VendorId = vendor.VendorID,
        Name = vendor.Name,
        VendorPriceBreakSheetPrices = sheetPricesViewModels
    };

    return View(viewModel);
}

因此正在加载下拉列表的数据，但未设置所选值。但价格值正在文本框中设置。

我不确定发生了什么。

Answer 1

请尝试使用此代码：

<%= Html.DropDownListFor(m => m.PaymentTypeId, 
    new SelectList(Model.PaymentTypes, "PaymentTypeID", "Name", Model.PaymentTypeId), 
    "- Select a Payment Type -")%>

此处有更详细的分析 - DropDownListFor not binding on Edit View with repeating items (List)。

加载编辑页面时未设置DropDown，但设置了其余的视图模型属性

1 个答案: