问题
In OrchardCMS v1.8.1.0, I receive the following error message when clicking on the Content link (/Admin/Contents/List) file name Modules\Orchard.MediaLibrary\Views\Parts\Document.SummaryAdmin.cshtml:
Object reference not set to an instance of an object.
Source Error:
Line 3: @{
Line 4: DocumentPart documentPart = Model.ContentPart;
//The following line throws the exception
Line 5: var mediaPart = ((ContentItem)Model.ContentItem).As<MediaPart>();
Line 6: }
Line 7:
Stack trace:
[NullReferenceException: Object reference not set to an instance of an object.]
ASP._Page_Modules_Orchard_MediaLibrary_Views_Parts_Document_SummaryAdmin_cshtml.Execute() in c:\inetpub\wwwroot\Modules\Orchard.MediaLibrary\Views\Parts\Document.SummaryAdmin.cshtml:5
System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +279
System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +124
System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +124
System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData) +146
Orchard.DisplayManagement.Descriptors.ShapeTemplateStrategy.ShapeTemplateBindingStrategy.Render(ShapeDescriptor shapeDescriptor, DisplayContext displayContext, HarvestShapeInfo harvestShapeInfo, HarvestShapeHit harvestShapeHit) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeTemplateStrategy\ShapeTemplateBindingStrategy.cs:149
Orchard.DisplayManagement.Descriptors.ShapeTemplateStrategy.<>c__DisplayClass28.<Discover>b__15(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeTemplateStrategy\ShapeTemplateBindingStrategy.cs:133
Orchard.DisplayManagement.Descriptors.<>c__DisplayClass5.<BoundAs>b__2(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAlterationBuilder.cs:56
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Process(ShapeBinding shapeBinding, IShape shape, DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:181
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Execute(DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:94
Orchard.DisplayManagement.Implementation.DisplayHelper.ShapeExecute(Object shape) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:86
Orchard.DisplayManagement.Implementation.DisplayHelper.TryInvoke(InvokeBinder binder, Object[] args, Object& result) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:30
CallSite.Target(Closure , CallSite , Object , Object ) +219
Orchard.Core.Shapes.CoreShapes.ContentZone(Object Display, Object Shape, TextWriter Output) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard.Web\Core\Shapes\CoreShapes.cs:274
[TargetInvocationException: Exception has been thrown by the target of an invocation.]
System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor) +0
System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments) +76
System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) +211
Orchard.DisplayManagement.Descriptors.ShapeAttributeStrategy.ShapeAttributeBindingStrategy.PerformInvoke(DisplayContext displayContext, MethodInfo methodInfo, Object serviceInstance) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAttributeStrategy\ShapeAttributeBindingStrategy.cs:65
Orchard.DisplayManagement.Descriptors.<>c__DisplayClass5.<BoundAs>b__2(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAlterationBuilder.cs:56
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Process(ShapeBinding shapeBinding, IShape shape, DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:185
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Execute(DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:94
Orchard.DisplayManagement.Implementation.DisplayHelper.ShapeExecute(Object shape) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:86
Orchard.DisplayManagement.Implementation.DisplayHelper.TryInvoke(InvokeBinder binder, Object[] args, Object& result) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:30
CallSite.Target(Closure , CallSite , Object , Object ) +220
ASP._Page_Core_Contents_Views_Content_SummaryAdmin_cshtml.Execute() in c:\inetpub\wwwroot\Core\Contents\Views\Content.SummaryAdmin.cshtml:13
System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +280
System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +125
System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +125
System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData) +147
Orchard.DisplayManagement.Descriptors.ShapeTemplateStrategy.ShapeTemplateBindingStrategy.Render(ShapeDescriptor shapeDescriptor, DisplayContext displayContext, HarvestShapeInfo harvestShapeInfo, HarvestShapeHit harvestShapeHit) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeTemplateStrategy\ShapeTemplateBindingStrategy.cs:151
Orchard.DisplayManagement.Descriptors.ShapeTemplateStrategy.<>c__DisplayClass28.<Discover>b__15(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeTemplateStrategy\ShapeTemplateBindingStrategy.cs:133
Orchard.DisplayManagement.Descriptors.<>c__DisplayClass5.<BoundAs>b__2(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAlterationBuilder.cs:56
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Process(ShapeBinding shapeBinding, IShape shape, DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:185
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Execute(DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:94
Orchard.DisplayManagement.Implementation.DisplayHelper.ShapeExecute(Object shape) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:86
Orchard.DisplayManagement.Implementation.DisplayHelper.TryInvoke(InvokeBinder binder, Object[] args, Object& result) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:30
CallSite.Target(Closure , CallSite , Object , Object ) +220
Orchard.Core.Shapes.CoreShapes.List(Object Display, TextWriter Output, IEnumerable`1 Items, String Tag, String Id, IEnumerable`1 Classes, IDictionary`2 Attributes, String ItemTag, IEnumerable`1 ItemClasses, IDictionary`2 ItemAttributes) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard.Web\Core\Shapes\CoreShapes.cs:687
[TargetInvocationException: Exception has been thrown by the target of an invocation.]
System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor) +0
System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments) +76
System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) +211
Orchard.DisplayManagement.Descriptors.ShapeAttributeStrategy.ShapeAttributeBindingStrategy.PerformInvoke(DisplayContext displayContext, MethodInfo methodInfo, Object serviceInstance) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAttributeStrategy\ShapeAttributeBindingStrategy.cs:65
Orchard.DisplayManagement.Descriptors.<>c__DisplayClass5.<BoundAs>b__2(DisplayContext displayContext) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Descriptors\ShapeAlterationBuilder.cs:56
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Process(ShapeBinding shapeBinding, IShape shape, DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:185
Orchard.DisplayManagement.Implementation.DefaultDisplayManager.Execute(DisplayContext context) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DefaultDisplayManager.cs:94
Orchard.DisplayManagement.Implementation.DisplayHelper.ShapeExecute(Object shape) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:86
Orchard.DisplayManagement.Implementation.DisplayHelper.TryInvoke(InvokeBinder binder, Object[] args, Object& result) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\DisplayManagement\Implementation\DisplayHelper.cs:30
CallSite.Target(Closure , CallSite , Object , Object ) +220
ASP._Page_Core_Contents_Views_Admin_List_cshtml.Execute() in c:\inetpub\wwwroot\Core\Contents\Views\Admin\List.cshtml:52
System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +280
System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +125
System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +125
Orchard.Mvc.ViewEngines.ThemeAwareness.<>c__DisplayClass7.<FindView>b__5(ViewContext viewContext, TextWriter writer, IViewDataContainer viewDataContainer) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\Mvc\ViewEngines\ThemeAwareness\LayoutAwareViewEngine.cs:60
System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +380
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +109
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +890
System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +97
System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +241
System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +29
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +111
System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +53
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +19
System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +51
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +111
Orchard.Mvc.Routes.HttpAsyncHandler.EndProcessRequest(IAsyncResult result) in z:\Builds\work\d1eb156ccc3cb14\src\Orchard\Mvc\Routes\ShellRoute.cs:159
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +606
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +288
回答1:
Looks like somehow the MediaPart isn't attached to the Document content type, while it expects it to be.
Attach the Media part to the Document content type, and set its Stereotype to 'Media' (both can be done in the dashboard).
来源：https://stackoverflow.com/questions/28671198/nullreference-exception-when-viewing-content-page-in-orchard-cms