從asp.net類調用MVC視圖會引發異常

Question

我想獲取MVC視圖的HTML。 正在從ASCX.CS類進行調用。 （我正在嘗試將MVC視圖注入ASPX頁面）。 我的ASPX頁面是動態創建的（控件是從后面的代碼中添加的）。

我在這里找到了答案的一部分。 唯一的問題是，此擴展方法是為MVC控制器類設計的。

在ASCX.CS的通話中我做了什么：

 fCatEve.Controllers.ASPXTestController test = new Controllers.ASPXTestController();
      string htmlView = test.RenderView("Index", null);

在此操作中，我唯一的問題是ControllerContext 。 我不知道如何設置此類，因此它將找到我要查找的局部視圖。

這是我正在使用的方法（來自上述頁面）：

public static class ControllerExtensions
{
    public static string RenderView(this Controller controller, string viewName, object model)
    {
        return RenderView(controller, viewName, new ViewDataDictionary(model));
    }

    public static string RenderView(this Controller controller, string viewName, ViewDataDictionary viewData)
    {
        RouteData routeData = new RouteData();
  routeData.Values.Add("controller", controller);
  var controllerContext = new ControllerContext { Controller = controller, RouteData = routeData };

  var viewResult = ViewEngines.Engines.FindView(controllerContext, viewName, null);

        StringWriter stringWriter;

        using (stringWriter = new StringWriter())
        {
            var viewContext = new ViewContext(
                controllerContext,
                viewResult.View,
                viewData,
                controllerContext.Controller.TempData,
                stringWriter);

            viewResult.View.Render(viewContext, stringWriter);
            viewResult.ViewEngine.ReleaseView(controllerContext, viewResult.View);
        }

        return stringWriter.ToString();
    }
}

例外是：

RouteData必須包含一個名為“ controller”的項目，該項目的字符串值為非空。

在嘗試了第一個答案之后，這是異常的堆棧跟蹤：

在System.Web.WebPages.DisplayModeProvider.GetDisplayMode（HttpContextBase context）在System.Web.Mvc.VirtualPathProviderViewEngine.GetPath（ControllerContext controllerContext，String [] location，String [] areaLocations，字符串locationPropertyName ，位於System.Web.Mvc.VirtualPathProviderViewEngine.FindView的字符串，字符串名稱，字符串controllerName，字符串cacheKeyPrefix，布爾useCache，字符串[]和searchedLocations）（位於System.Web.Mvc.ViewEngineCollection的ControllerContext controllerContext，字符串viewName，字符串masterName，布爾useCache）。 。<> c__DisplayClass6.b__4（IViewEngine e）在System.Web.Mvc.ViewEngineCollection.FindView（ControllerContext controllerContext，String viewName，String masterName）在System.Web.Mvc.ViewEngineCollection.FindView（Controller2 controller，Boolean trackSearchedPaths） fCatEve.Helpers.ControllerExtensions.RenderView（控制器控制器，字符串viewName，ViewDataDictionary viewData）在C：\\ ProjectsG_Test-KOPIJA \\ fCatEve03 \\ Solution \\ fCatEve \\ fCatEve \\ Helpers \\ ControllerExtensions.cs：fCatEve.Controls.KoledarReception.PutValuesToTabControlEVEBEVEN（Panel paControl，REFields REField）的第43行位於C：\\ ProjectsG_Test-KOPIJA \\ fCatEve03 \\ Solution \\ fCatEve \\ E \\ CatEve \\ Ec ascx.cs：C：\\ ProjectsG_Test中的fCatEve.Controls.KoledarReception.PutValuesToTabControl（）的第2747行-KOPIJA \\ fCatEve03 \\ Solution \\ fCatEve \\ fCatEve \\ wf \\ Controls \\ KoledarReception.ascx.cs：eC的第2710行。 .Page_Load（Object sender，EventArgs e）in C：\\ ProjectsG_Test-KOPIJA \\ fCatEve03 \\ Solution \\ fCatEve \\ fCatEve \\ wf \\ Controls \\ KoledarReception.ascx.cs：System.Web.Util.CalliEventHandlerDelegateProxy.Callback的817行，System.Web.UI.Control.OnLoad上的EventArgs e）（System.Web.UI.Control.LoadRecursive（）上System.Web.UI.Control.LoadRecursive（）的System.Web.UI.Control.LoadRecursive（）的EventArgs e） System.Web.UI.Control.LoadRecursive（）的System.Web.UI.Control.LoadRecursive（）的System.Web.UI.Page.ProcessRequ的.LoadRecursive（） estMain（Boolean includeStagesBeforeAsyncPoint，Boolean includeStagesAfterAsyncPoint）

Answer 1

這是我用於其中一個單元測試的示例代碼，該代碼應該生成PDF文件，不確定是否對您有好處。

var controller = new MyAwesomePdfController();

var httpRequest = new HttpRequest("", "http://mySomething", "");
var stringWriter = new StringWriter();
var httpResponse = new HttpResponse(stringWriter);
var routeData = new RouteData();
routeData.Values.Add("Controller", "MyAwesomePdf");  //must match your Controller name
routeData.Values.Add("Action", "Receipt");  //must match your Action name

var httpContextMock = new HttpContext(httpRequest, httpResponse)
{
    //this is probably irrelevant to you, can set user principal here
    //User = new GenericPrincipal(
    //  new GenericIdentity(username),
    //  userRoles //new string[0]
    //)
};

controller.ControllerContext = new ControllerContext(new HttpContextWrapper(httpContextMock), routeData, controller);

var receiptId = 1234;
var pdfResult = await controller.Receipt(receiptId) as ViewAsPdf;  //should return a pdf file

Answer 2

我重寫了該調用（最重要的是：HttpContext.Current，稍后在MVC中使用）：

fCatEve.Controllers.ASPXTestController test = new Controllers.ASPXTestController();
      string htmlView = test.RenderView("Index", null, HttpContext.Current);

我還稍微重寫了這兩種方法：

   public static string RenderView(this Controller controller, string viewName, object model, HttpContext currentContext)
    {
      return RenderView(controller, viewName, new ViewDataDictionary(model), currentContext);
    }


    public static string RenderView(this Controller controller, string viewName, ViewDataDictionary viewData, HttpContext currentContext)
    {
      var routeData = new RouteData();
      routeData.Values.Add("Controller", "ASPXTest");  //must match your Controller name
      routeData.Values.Add("Action", "Test");  //must match your Action name

      HttpContextWrapper wrapper = new HttpContextWrapper(currentContext);
      controller.ControllerContext = new ControllerContext(wrapper, routeData, controller);
      var viewResult = ViewEngines.Engines.FindView(controller.ControllerContext, viewName, null);

      StringWriter stringWriter;
      viewData = new ViewDataDictionary();


      using (stringWriter = new StringWriter())
      {
        var viewContext = new ViewContext(
            controller.ControllerContext,
            viewResult.View,
            viewData,
            controller.ControllerContext.Controller.TempData,
            stringWriter);

        viewResult.View.Render(viewContext, stringWriter);
        viewResult.ViewEngine.ReleaseView(controller.ControllerContext, viewResult.View);
      }

      return stringWriter.ToString();
    }