httpsost在mvc3 razor vb.net中不返回任何复杂对象

时间:2012-06-14 16:17:47

标签: asp.net-mvc vb.net asp.net-mvc-3 web-applications razor

我的MVC3 vb.net应用程序出现问题。当我尝试将我所做的更改发布到控制器时,模型不会发送到控制器。

我曾尝试关注许多帖子,例如this onethis one,但我不确定如何在我的应用程序中实现它们,因为我的模型没有发送IEnumerable类型。

最后,我只希望模型为每个批次返回一个值,该值是我将保存到数据库的值。

当我发布模型并尝试发送到控制器时,页面通过post发送以下内容:

Client=2&Datacenters=20&BatchesForAssignation[0].CenterID=4&BatchesForAssignation[1].CenterID=20&BatchesForAssignation[1].DatacenterID=14...

但我不知道如何将此查询字符串转换为 BatchesForAssignation 对象,将其分配给模型并发送给控制器。

注意:查询字符串中显示的客户端数据中心的值不会在控制器中使用。我需要 BatchesForAssignation [n] .CenterID 部分。

你能指点我找到解决方案吗?

这是我在MVC应用程序中使用的对象(代码压缩):

批处理:

Public class Batch
    public property ID as integer
    public property CenterID as integer
    public property name as string
end class

中心(此对象只存储将分配给批次的所有中心列表。名称只是为了在下拉列表中显示名称):

Public class Center
    public property ID as integer
    public property name as string
end class

(还有一个Batchlist和一个Centerlist对象,它们作为从CollectionBase继承的集合,存储所有Batch和Center对象。如果你需要类定义,请告诉我,但非常明确。)

模型如下

Public class ProcessingModel
    public property BatchesForAssignation as BatchList
    public property Datacenters as CenterList
End class

控制器如下:

<HttpGet()>
<Authorize()> _
Public Function AssignToDataCenters() As ActionResult
    Dim model As New ProcessingModel
    Dim BatchHandler As New BatchControl

    'This line will get the list of batches without datacenter
    model.BatchesForAssignation = BatchHandler.GetBatchesAvailable(ConnectionString)

    'This method will get the list of Datacenters available
    model.Datacenters=BatchHandler.GetDatacenters(ConnectionString)
    return View(model)
End Function

HttpPost(实际上这不起作用,因为模型返回一个空模型):

<HttpPost()>
<Authorize()> _
Public Function AssignToDataCenters(ByVal Model as ProcessingModel) As ActionResult
    Dim BatchHandler As New BatchControl
    Dim SaveResult as Boolean=false

    'This line will get the list of batches without datacenter
    model.BatchesForAssignation = BatchHandler.GetBatchesAvailable(ConnectionString)

    'This method save the information returned by the model
    SaveResult=BatchHandler.UpdateBatches(model)

    ViewBag("Result")=SaveResult
    Return View(model)
End Function

视图如下(是强类型视图):

@ModelType MVCAdmin.ProcessingModel

@Code
    ViewData("Title") = "Assign Batches To centers"
End Code

@Using Html.BeginForm()
    @<table id="tblAvailableBatches">
        <thead>
            <tr>
                <th>Assign batch to:</th>
                <th>Name</th>
            </tr>
        </thead>
        <tbody>
            @code
                For i As Integer = 0 To Model.BatchesForAssignation.Count - 1
                    Dim a As Integer = i
                    @<tr>
                        <td>@Html.DropDownListFor(Function(m) m.BatchesForAssignation(a).CenterID, New SelectList(Model.Datacenters, "ID", "name", model.BatchesForAssignation(i).CenterID), " ")</td>
                        <td>@Model.BatchesForAssignation(i).name</td>
                    </tr>        
                Next
            End Code
        </tbody>
    </table>
    <input type="button" value="Apply changes" id="btnApply" />
End Using

提前致谢

更新2012-06-14:

在做了一些研究之后,我发现我可以使用request.Form解析控制器中的查询字符串。我可以解析视图发送的结果。但是查询字符串的格式为BatchesForAssignation[0].CenterIDBatchesForAssignation[1].CenterIDBatchesForAssignation[2].CenterID等等......

是否有更好的方法“自动”执行此操作,以便模型解析查询字符串并将解析后的对象发送到控制器?

再次......提前致谢

1 个答案:

答案 0 :(得分:1)

在审核this question后,我发现创建模型并将其发送到控制器的最佳方法是创建CustomModelBinder(来自IModelBinder接口)并解析表单使用BindModel属性在controllerContext.HttpContext.Request.Form方法上查询字符串。像这样:

Public Class ProcessingModelBinder
    implements IModelBinder

    public Function BindModel(controllerContext As System.Web.Mvc.ControllerContext, bindingContext As System.Web.Mvc.ModelBindingContext) As Object
        dim model as ProcessingModel = if(nothing.equals(bindingContext.Model),directcast(bindingContext.Model,directcast(DependencyResolver.Current.GetService(typeof(ProcessingModel))
        dim Keys as string()=controllerContext.HttpContext.Request.Form.AllKeys

        for each key in Keys
            'Fill the model required parameters
        Next

        return model
End Function

最后在global.asax文件中注册新的模型构建器

Sub Application_Start()
    AreaRegistration.RegisterAllAreas()
    ModelBinders.Binders.Add(typeof(ProcessingModel),New ProcessingModelBinder())
    RegisterGlobalFilters(GlobalFilters.Filters)
    RegisterRoutes(RouteTable.Routes)
End Sub

我希望这有助于某人

此致