Question

I am using MvcSiteMapProvider to create menu for my web site. It was working properly but suddenly failed with error:

System.NullReferenceException: Object reference not set to an instance of an object.

and here is the stack trace:

[NullReferenceException: Object reference not set to an instance of an object.]

MvcSiteMapProvider.AuthorizeAttributeAclModule.IsAccessibleToUser(IControllerTypeResolver controllerTypeResolver, DefaultSiteMapProvider provider, HttpContext context, SiteMapNode node) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\AuthorizeAttributeAclModule.cs:80
   MvcSiteMapProvider.DefaultAclModule.IsAccessibleToUser(IControllerTypeResolver controllerTypeResolver, DefaultSiteMapProvider provider, HttpContext context, SiteMapNode node) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\DefaultAclModule.cs:61
   MvcSiteMapProvider.DefaultSiteMapProvider.IsAccessibleToUser(HttpContext context, SiteMapNode node) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\DefaultSiteMapProvider.cs:178
   System.Web.SiteMapNode.IsAccessibleToUser(HttpContext context) +17
   System.Web.StaticSiteMapProvider.GetChildNodes(SiteMapNode node) +378
   System.Web.SiteMapNode.get_ChildNodes() +30
   System.Web.SiteMapNode.get_HasChildNodes() +10
   MvcSiteMapProvider.Web.Html.MenuHelper.BuildModel(MvcSiteMapHtmlHelper helper, SiteMapNode startingNode, Boolean startingNodeInChildLevel, Boolean showStartingNode, Int32 maxDepth, Boolean drillDownToCurrent) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\Web\Html\MenuHelper.cs:293
   MvcSiteMapProvider.Web.Html.MenuHelper.Menu(MvcSiteMapHtmlHelper helper, String templateName, SiteMapNode startingNode, Boolean startingNodeInChildLevel, Boolean showStartingNode, Int32 maxDepth, Boolean drillDownToCurrent) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\Web\Html\MenuHelper.cs:234
   MvcSiteMapProvider.Web.Html.MenuHelper.Menu(MvcSiteMapHtmlHelper helper) in c:\Projects\Codeplex\TFS10\mvcsitemap\Branches\3.1.0\src\MvcSiteMapProvider\MvcSiteMapProvider\Web\Html\MenuHelper.cs:31

I cannot think of any changes I made to introduce this error. The only changes made were due to results by using StyleCop (e.g. alter order of usings, methods, properties, etc.). Any idea?

Answer 1

if you don’t need security trimming (e.g. permissions/roles for the nodes) set securityTrimmingEnabled=”false” on the registration of the sitemap provider in your web.config and you should no longer have this error.

I’ve raised an issue on http://mvcsitemap.codeplex.com/workitem/6337 but it might not specifically be your problem.