asp.net-mvc - MVC 发布 IPgedList

Question

我有以下 PagedListModel:

public class PagedClientViewModel
{
    public int? Page { get; set; }
    public PagedList.IPagedList<ClientViewModel> Clients { get; set; }               
}

public class ClientViewModel
{        
    public string ClientNumber { get; set; }
    public bool UseThisClient{ get; set; }
}

我的观点如下:

@using (Html.BeginForm("Index", "Home", FormMethod.Get, new { id = "Form" }))
{
    @foreach (var item in Model.Clients)
    {
       @Html.DisplayFor(modelItem => item.ClientNumber)
       @Html.CheckBoxFor(modelItem => item.UseThisClient)
    }    

 @Html.HiddenFor(model => model.Clients)            
}

Controller 操作:

 public ActionResult Index(PagedClientViewModel model)
 {
  //...process all clients in the list
 }

我想将模型发布回 Controller ，以便我可以处理已勾选的复选框，但出现以下错误:我明白该错误是因为我正在回发接口(interface)，但我不能找到解决办法。我怎样才能得到这份工作？

Cannot create an instance of an interface. at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
at System.Activator.CreateInstance(Type type, Boolean nonPublic)
at System.Activator.CreateInstance(Type type) at System.Web.Mvc.DefaultModelBinder.CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) at System.Web.Mvc.DefaultModelBinder.BindSimpleModel(ControllerContext controllerContext, ModelBindingContext bindingContext, ValueProviderResult valueProviderResult) at System.Web.Mvc.DefaultModelBinder.BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) at System.Web.Mvc.DefaultModelBinder.GetPropertyValue(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor, IModelBinder propertyBinder)
at System.Web.Mvc.DefaultModelBinder.BindProperty(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor) at System.Web.Mvc.DefaultModelBinder.BindProperties(ControllerContext controllerContext, ModelBindingContext bindingContext) at System.Web.Mvc.DefaultModelBinder.BindComplexElementalModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Object model)
at System.Web.Mvc.DefaultModelBinder.BindComplexModel(ControllerContext controllerContext, ModelBindingContext bindingContext) at System.Web.Mvc.DefaultModelBinder.BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) at System.Web.Mvc.ControllerActionInvoker.GetParameterValue(ControllerContext controllerContext, ParameterDescriptor parameterDescriptor) at System.Web.Mvc.ControllerActionInvoker.GetParameterValues(ControllerContext controllerContext, ActionDescriptor actionDescriptor) at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c_DisplayClass25.b_1e(AsyncCallback asyncCallback, Object asyncState) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult1.Begin(AsyncCallback
callback, Object state, Int32 timeout) at
System.Web.Mvc.Async.AsyncControllerActionInvoker.BeginInvokeAction(ControllerContext
controllerContext, String actionName, AsyncCallback callback, Object
state) at
System.Web.Mvc.Controller.<>c__DisplayClass1d.<BeginExecuteCore>b__17(AsyncCallback
asyncCallback, Object asyncState) at
System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult1.Begin(AsyncCallback callback, Object state, Int32 timeout) at System.Web.Mvc.Controller.BeginExecuteCore(AsyncCallback callback, Object state) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult1.Begin(AsyncCallback
callback, Object state, Int32 timeout) at
System.Web.Mvc.Controller.BeginExecute(RequestContext requestContext,
AsyncCallback callback, Object state) at
System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.BeginExecute(RequestContext
requestContext, AsyncCallback callback, Object state) at
System.Web.Mvc.MvcHandler.<>c__DisplayClass8.<BeginProcessRequest>b__2(AsyncCallback
asyncCallback, Object asyncState) at
System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult1.Begin(AsyncCallback callback, Object state, Int32 timeout) at System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) at System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) at System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

Answer 1

解决此问题的方法是将分页元数据作为单独的属性传递，并在 View 中重建 IPgedList。就像下面这样

public class PagedClientViewModel
{
    public int? Page { get; set; }
    public List<ClientViewModel> Clients { get; set; }
    public IPagedList PagingMetaData { get; set; } 
}

生成元数据

pagedClientViewModel.PagingMetaData = new StaticPagedList<ClientViewModel>(pagedClientViewModel.Clients, pageIndex, pageSize, TotalClients).GetMetaData();

在 View 中构造寻呼机

<div style="text-align: center">
    @Html.PagedListPager(new StaticPagedList<ClientViewModel>(Model.Clients, Model.PagingMetaData), page => Url.Action("<actionname>", new { page }), PagedListRenderOptions.Classic)
</div>