Unable to set property 'AppAssembly' on object of type 'Microsoft.AspNetCore.Components.Routing.Router'

[danroth27]

Repro steps:

• Install latest preview4 nightly build (3.0.100-preview4-010963)
• dotnet new razorcomponents
• dotnet run
• Browse to https://localhost:5001

      Unhandled exception rendering component: Unable to set property 'AppAssembly' on object of type 'Microsoft.AspNetCore.Components.Routing.Router'. The error was: Unable to cast object of type 'System.String' to type 'System.Reflection.Assembly'.
System.InvalidOperationException: Unable to set property 'AppAssembly' on object of type 'Microsoft.AspNetCore.Components.Routing.Router'. The error was: Unable to cast object of type 'System.String' to type 'System.Reflection.Assembly'. ---> System.InvalidCastException: Unable to cast object of type 'System.String' to type 'System.Reflection.Assembly'.
   at Microsoft.AspNetCore.Components.Reflection.MemberAssignment.PropertySetter`2.SetValue(Object target, Object value)
   at Microsoft.AspNetCore.Components.ParameterCollectionExtensions.SetParameterProperties(ParameterCollection& parameterCollection, Object target)
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.Components.ParameterCollectionExtensions.SetParameterProperties(ParameterCollection& parameterCollection, Object target)
   at Microsoft.AspNetCore.Components.Routing.Router.SetParametersAsync(ParameterCollection parameters)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterCollection parameters)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewComponentFrame(DiffContext& diffContext, Int32 frameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewSubtree(DiffContext& diffContext, Int32 frameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InsertNewFrame(DiffContext& diffContext, Int32 newFrameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.ComputeDiff(Renderer renderer, RenderBatchBuilder batchBuilder, Int32 componentId, ArrayRange`1 oldTree, ArrayRange`1 newTree)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.RenderInExistingBatch(RenderQueueEntry renderQueueEntry)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.ProcessRenderQueue()
   at Microsoft.AspNetCore.Components.Rendering.Renderer.AddToRenderQueue(Int32 componentId, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.RenderHandle.Render(RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.ComponentBase.StateHasChanged()
   at Microsoft.AspNetCore.Components.ComponentBase.CallOnParametersSetAsync()
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
info: Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure.PageActionInvoker[4]
      Executed page /Index in 144.857ms
fail: Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware[1]
      An unhandled exception has occurred while executing the request.
System.InvalidOperationException: Unable to set property 'AppAssembly' on object of type 'Microsoft.AspNetCore.Components.Routing.Router'. The error was: Unable to cast object of type 'System.String' to type 'System.Reflection.Assembly'. ---> System.InvalidCastException: Unable to cast object of type 'System.String' to type 'System.Reflection.Assembly'.
   at Microsoft.AspNetCore.Components.Reflection.MemberAssignment.PropertySetter`2.SetValue(Object target, Object value)
   at Microsoft.AspNetCore.Components.ParameterCollectionExtensions.SetParameterProperties(ParameterCollection& parameterCollection, Object target)
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.Components.ParameterCollectionExtensions.SetParameterProperties(ParameterCollection& parameterCollection, Object target)
   at Microsoft.AspNetCore.Components.Routing.Router.SetParametersAsync(ParameterCollection parameters)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterCollection parameters)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewComponentFrame(DiffContext& diffContext, Int32 frameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewSubtree(DiffContext& diffContext, Int32 frameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InsertNewFrame(DiffContext& diffContext, Int32 newFrameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.ComputeDiff(Renderer renderer, RenderBatchBuilder batchBuilder, Int32 componentId, ArrayRange`1 oldTree, ArrayRange`1 newTree)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.RenderInExistingBatch(RenderQueueEntry renderQueueEntry)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.ProcessRenderQueue()
   at Microsoft.AspNetCore.Components.Rendering.Renderer.AddToRenderQueue(Int32 componentId, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.RenderHandle.Render(RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.ComponentBase.StateHasChanged()
   at Microsoft.AspNetCore.Components.ComponentBase.CallOnParametersSetAsync()
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
   at Microsoft.AspNetCore.Components.Server.Circuits.CircuitPrerenderer.CircuitHost_UnhandledException(Object sender, UnhandledExceptionEventArgs e)
   at Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost.Renderer_UnhandledException(Object sender, Exception e)
   at Microsoft.AspNetCore.Components.Browser.Rendering.RemoteRenderer.HandleException(Exception exception)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.AddToPendingTasks(Task task)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterCollection parameters)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.RenderRootComponentAsync(Int32 componentId, ParameterCollection initialParameters)
   at Microsoft.AspNetCore.Components.Rendering.HtmlRenderer.CreateInitialRenderAsync(Type componentType, ParameterCollection initialParameters)
   at Microsoft.AspNetCore.Components.Rendering.HtmlRenderer.RenderComponentAsync(Type componentType, ParameterCollection initialParameters)
   at Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost.<>c__DisplayClass41_0.<<PrerenderComponentAsync>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c__DisplayClass11_0`1.<<InvokeAsync>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Components.Server.Circuits.CircuitPrerenderer.PrerenderComponentAsync(ComponentPrerenderingContext prerenderingContext)
   at Microsoft.AspNetCore.Components.Server.Circuits.CircuitPrerenderer.PrerenderComponentAsync(ComponentPrerenderingContext prerenderingContext)
   at Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelperRazorComponentExtensions.RenderComponentAsync[TComponent](IHtmlHelper htmlHelper, Object parameters)
   at RazorComponentsApp1.Pages.Pages_Index.<ExecuteAsync>b__22_1() in C:\Users\daroth\Desktop\preview4\RazorComponentsApp1\Pages\Index.cshtml:line 22
   at Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperExecutionContext.SetOutputContentAsync()
   at RazorComponentsApp1.Pages.Pages_Index.ExecuteAsync()
   at Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageCoreAsync(IRazorPage page, ViewContext context)
   at Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageAsync(IRazorPage page, ViewContext context, Boolean invokeViewStarts)
   at Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context)
   at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, String contentType, Nullable`1 statusCode)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultAsync(IActionResult result)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeNextResultFilterAsync[TFilter,TFilterAsync]()
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext[TFilter,TFilterAsync](State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultFilters()
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeNextResourceFilter()
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeAsync()
   at Microsoft.AspNetCore.Routing.EndpointRoutingMiddleware.Invoke(HttpContext httpContext)
   at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

[danroth27]

@rynowak Known issue?

[pranavkm]

Dup of #8825