Question

我正在尝试使用“伪控制器上下文”将MVC局部视图（包含Kendo Grid）渲染为html字符串..

我想知道是否有办法为此创建合适的假控制器..所以我可以从静态方法 访问MVC局部视图（包含Kendo网格）。

对此有任何帮助表示赞赏。在此先感谢!!

我一直收到此错误：

值不能为空。参数名称：controllerContext 描述：执行当前Web请求期间发生未处理的异常。请查看堆栈跟踪了解更多信息有关错误的信息以及它在代码中的起源。

Exception Details: System.ArgumentNullException: Value cannot be null. Parameter name: controllerContext Source Error: Line 8: @(Html.Kendo().Grid<SimpleKendoModelData>()

堆栈追踪：

[ArgumentNullException: Value cannot be null. Parameter name: controllerContext] System.Web.Mvc.ChildActionValueProviderFactory.GetValueProvider(ControllerContext controllerContext) +137 System.Web.Mvc.ValueProviderFactoryCollection.GetValueProvider(ControllerContext controllerContext) +80 System.Web.Mvc.ControllerBase.get_ValueProvider() +39 Kendo.Mvc.UI.Grid`1.ProcessDataSource() +254 Kendo.Mvc.UI.Grid`1.WriteHtml(HtmlTextWriter writer) +818 Kendo.Mvc.UI.WidgetBase.ToHtmlString() +102 Kendo.Mvc.UI.Fluent.WidgetBuilderBase`2.ToHtmlString() +15 System.Web.WebPages.WebPageBase.Write(Object value) +103 ASP._Page_Views_Reporting_ReportElement_SimpleKendoGrid_cshtml.Execute() in c:\Users\xxx\Documents\Visual Studio 2015\Projects\xxx\Views\Reporting\ReportElement_SimpleKendoGrid.cshtml:8 System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +253 System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +148 System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +122 xxx.Api.Ui.Helpers.ViewRenderer.RenderViewToStringInternal(String viewPath, Object model, Boolean partial) in C:\Users\xxx\Documents\Visual Studio 2015\Projects\xxx\Helpers\ViewRenderer.cs:218 xxx.Api.Ui.Helpers.ViewRenderer.RenderPartialView(String viewPath, Object model) in C:\Users\xxx\Documents\Visual Studio 2015\Projects\xxx\Helpers\ViewRenderer.cs:81 xxx.Api.Ui.Helpers.ViewRenderer.RenderPartialView(String viewPath, Object model, ControllerContext controllerContext) in C:\Users\xxx\Documents\Visual Studio 2015\Projects\xxx\Helpers\ViewRenderer.cs:149 xxx.Api.Ui.Controllers.ReportingController.Test() in C:\Users\xxx\Documents\Visual Studio 2015\Projects\xxx\Controllers\ReportingController.cs:86 lambda_method(Closure , ControllerBase , Object[] ) +87 System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +229 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35 System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +39 System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +67 System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +42 System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d() +72 System.Web.Mvc.Async.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +386 System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +42 System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +38 System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +186 System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +38 System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +29 System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +65 System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +53 System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +36 System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38 System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +44 System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +65 System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +399 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +157

这是我在控制器中的测试方法：

[AllowAnonymous] public ActionResult Test() { var model = new SimpleKendoModel(); for (int x = 0; x < 10; x++) { var result = new SimpleKendoModelData(); result.Data = x; model.Results.Add(result); } var currentContext = ControllerExtensions.GetFakeControllerContext(); //This commented out code works //var html = ViewRenderer.RenderPartialView("~/Views/Reporting/ReportElement_SimpleKendoGrid.cshtml", model, ControllerContext); var html = ViewRenderer.RenderPartialView("~/Views/Reporting/ReportElement_SimpleKendoGrid.cshtml", model, currentContext); return View(); }

ControllerExtensions类：

public static class ControllerExtensions { public static ControllerContext GetFakeControllerContext() { var currentContext = new HttpContext(new HttpRequest(null, "http://tempuri.org", null), new HttpResponse(null)); var st = new StringWriter(); var context = new HttpContextWrapper(currentContext); var routeData = new RouteData(); routeData.Values.Add("controller", "someValue"); var controllerContext = new ControllerContext(new RequestContext(context, routeData), new FakeController()); return controllerContext; } }

查看渲染器类：

// Read: https://weblog.west-wind.com/posts/2012/may/30/rendering-aspnet-mvc-views-to-string /// <summary> /// Class that renders MVC views to a string using the /// standard MVC View Engine to render the view. /// </summary> public class ViewRenderer { /// <summary> /// Required Controller Context /// </summary> protected ControllerContext Context { get; set; } /// <summary> /// Initializes the ViewRenderer with a Context. /// </summary> /// <param name="controllerContext"> /// If you are running within the context of an ASP.NET MVC request pass in /// the controller's context. /// Only leave out the context if no context is otherwise available. /// </param> public ViewRenderer(ControllerContext controllerContext = null) { // Create a known controller from HttpContext if no context is passed if (controllerContext == null) { if (HttpContext.Current != null) { var currentContext = HttpContext.Current; var context = new HttpContextWrapper(currentContext); var routeData = new RouteData(); controllerContext = new ControllerContext(new RequestContext(context, routeData), new FakeController()); } else throw new InvalidOperationException( "ViewRenderer must run in the context of an ASP.NET " + "Application and requires HttpContext.Current to be present."); } Context = controllerContext; } /// <summary> /// Renders a full MVC view to a string. Will render with the full MVC /// View engine including running _ViewStart and merging into _Layout /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to render the view with</param> /// <returns>String of the rendered view or null on error</returns> public string RenderView(string viewPath, object model) { return RenderViewToStringInternal(viewPath, model, false); } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <returns>String of the rendered view or null on error</returns> public string RenderPartialView(string viewPath, object model) { return RenderViewToStringInternal(viewPath, model, true); } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <param name="controllerContext">Active Controller context</param> /// <returns>String of the rendered view or null on error</returns> public static string RenderView(string viewPath, object model, ControllerContext controllerContext) { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderView(viewPath, model); } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <param name="controllerContext">Active Controller context</param> /// <param name="errorMessage">optional out parameter that captures an error message instead of throwing</param> /// <returns>String of the rendered view or null on error</returns> public static string RenderView(string viewPath, object model, ControllerContext controllerContext, out string errorMessage) { errorMessage = null; try { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderView(viewPath, model); } catch (Exception ex) { errorMessage = ex.GetBaseException().Message; } return null; } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <param name="controllerContext">Active controller context</param> /// <returns>String of the rendered view or null on error</returns> public static string RenderPartialView(string viewPath, object model, ControllerContext controllerContext) { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderPartialView(viewPath, model); } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <param name="controllerContext">Active controller context</param> /// <param name="errorMessage">optional output parameter to receive an error message on failure</param> /// <returns>String of the rendered view or null on error</returns> public static string RenderPartialView(string viewPath, object model, ControllerContext controllerContext, out string errorMessage) { errorMessage = null; try { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderPartialView(viewPath, model); } catch (Exception ex) { errorMessage = ex.GetBaseException().Message; } return null; } /// <summary> /// Internal method that handles rendering of either partial or /// or full views. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">Model to render the view with</param> /// <param name="partial">Determines whether to render a full or partial view</param> /// <returns>String of the rendered view</returns> protected string RenderViewToStringInternal(string viewPath, object model, bool partial = false) { // first find the ViewEngine for this view ViewEngineResult viewEngineResult = null; if (partial) viewEngineResult = ViewEngines.Engines.FindPartialView(Context, viewPath); else viewEngineResult = ViewEngines.Engines.FindView(Context, viewPath, null); if (viewEngineResult == null) throw new FileNotFoundException("ViewCouldNotBeFound"); // get the view and attach the model to view data var view = viewEngineResult.View; Context.Controller.ViewData.Model = model; string result = null; using (var sw = new StringWriter()) { var ctx = new ViewContext(Context, view, Context.Controller.ViewData, Context.Controller.TempData, sw); view.Render(ctx, sw); result = sw.ToString(); } return result; } /// <summary> /// Creates an instance of an MVC controller from scratch /// when no existing ControllerContext is present /// </summary> /// <typeparam name="T">Type of the controller to create</typeparam> /// <returns></returns> public static T CreateController<T>(RouteData routeData = null) where T : Controller, new() { T controller = new T(); // Create an MVC Controller Context HttpContextBase wrapper = null; if (HttpContext.Current != null) wrapper = new HttpContextWrapper(System.Web.HttpContext.Current); //else // wrapper = CreateHttpContextBase(writer); if (routeData == null) routeData = new RouteData(); if (!routeData.Values.ContainsKey("controller") && !routeData.Values.ContainsKey("Controller")) routeData.Values.Add("controller", controller.GetType().Name .ToLower() .Replace("controller", "")); controller.ControllerContext = new ControllerContext(wrapper, routeData, controller); return controller; } }

〜/ Views / Reporting / ReportElement_SimpleKendoGrid.cshtml局部视图：

@{ ViewBag.Title = "Index"; Layout = "~/Views/Shared/_ReportTemplateLayout.cshtml"; } @model SimpleKendoModel @(Html.Kendo().Grid<SimpleKendoModelData>() .Name("Results") .BindTo(Model.Results) .Columns(columns => { columns.Bound(x => x.Data).Title("Data").Width(250); }) .DataSource(datasource => datasource .Ajax() .PageSize(5000) .ServerOperation(false) ) )

〜/查看/共享/ _ReportTemplateLayout.cshtml：

@RenderBody()

MVC部分视图模型：

public class SimpleKendoModel { public SimpleKendoModel() { Results = new List<SimpleKendoModelData>(); } public List<SimpleKendoModelData> Results { get; set;} } public class SimpleKendoModelData { public SimpleKendoModelData() { Data = 0; } public int Data { get; set; } }

This is the partial view result

Answer 1

感谢此帖：

Setting HttpContext.Current.Session in a unit test

我实际上已经解决了这个问题..

使用下面的类，我能够使用MVC Razor局部视图（包含Kendo网格）成功创建模板HTML以用于电子邮件模板..并允许我从静态方法调用它。

我创建了一个名为 ControllerExtensions

的类

public static class ControllerExtensions
{
    public static ControllerContext GetFakeControllerContext()
    {
        HttpContext.Current = HttpContext.Current ?? GetFakeHttpContext();

        var currentContext = HttpContext.Current;

        var controller = CreateController<FakeController>();

        var st = new StringWriter();
        var context = new HttpContextWrapper(currentContext);
        var routeData = GetFakeRouteData(controller);

        var controllerContext = new ControllerContext(new RequestContext(context, routeData), controller);

        return controllerContext;
    }

    public static HttpContext GetFakeHttpContext()
    {
        var httpRequest = new HttpRequest("", "http://stackoverflow/", "");
        var stringWriter = new StringWriter();
        var httpResponse = new HttpResponse(stringWriter);
        var httpContext = new HttpContext(httpRequest, httpResponse);

        var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
                                                new HttpStaticObjectsCollection(), 10, true,
                                                HttpCookieMode.AutoDetect,
                                                SessionStateMode.InProc, false);

        httpContext.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
                                    BindingFlags.NonPublic | BindingFlags.Instance,
                                    null, CallingConventions.Standard,
                                    new[] { typeof(HttpSessionStateContainer) },
                                    null)
                            .Invoke(new object[] { sessionContainer });

        return httpContext;
    }

    public static RouteData GetFakeRouteData(Controller controller)
    {
        var routeData = new RouteData();

        if (!routeData.Values.ContainsKey("controller") && !routeData.Values.ContainsKey("Controller"))
            routeData.Values.Add("controller", controller.GetType().Name
                                                        .ToLower()
                                                        .Replace("controller", ""));

        return routeData;
    }

    public static T CreateController<T>(RouteData routeData = null)
        where T : Controller, new()
    {
        T controller = new T();

        // Create an MVC Controller Context
        var wrapper = new HttpContextWrapper(System.Web.HttpContext.Current);

        if (routeData == null)
            routeData = new RouteData();

        if (!routeData.Values.ContainsKey("controller") && !routeData.Values.ContainsKey("Controller"))
            routeData.Values.Add("controller", controller.GetType().Name
                                                        .ToLower()
                                                        .Replace("controller", ""));

        controller.ControllerContext = new ControllerContext(wrapper, routeData, controller);
        return controller;
    }
}

public class FakeController : Controller
{

}

并按以下方式使用：

public static string GetHtml()
{
    var model = new SimpleKendoModel();
    for (int x = 0; x < 10; x++)
    {
        var result = new SimpleKendoModelData();
        result.Data = x;
        model.Results.Add(result);
    }

    var currentContext = ControllerExtensions.GetFakeControllerContext();

    var html = ViewRenderer.RenderPartialView("~/Views/Reporting/ReportElement_SimpleKendoGrid.cshtml", model, currentContext);

    return html;
}

如何将MVC局部视图（包含Kendo Grid）渲染为html字符串

1 个答案: