Using SPContext anonymously

For one of our projects – a public facing site – we developed a custom control which renders an image. The control is placed within the MasterPage and the URL of the image to render is being determined by some rules. One of these rules is related to the PageLayout being used by the Page the user is visiting. For this rule to evaluate, we need the name of the PageLayout.

The most basic code I could think of for retrieving this value was the following

SPSecurity.RunWithElevatedPrivileges(delegate() {
  PublishingPage currentPage = PublishingPage.GetPublishingPage(SPContext.Current.ListItem);
  string pageLayoutName = currentPage.Layout.Name;
});


Running this code using Windows authentication works fine. Running this code in anonymous context however caused a challenge to appear when executing the line where pageLayoutName is assigned a value. The reason for this is that some objects referenced in the SPContext object were already created outside of the elevated context. So, to retrieve the name of the current PageLayout, I had to instantiate most of the objects needed to get to the PageLayout object manually. The following code worked for me:

SPSecurity.RunWithElevatedPrivileges(delegate() {
  using (SPSite siteCollection = new SPSite(SPContext.Current.Web.Site.Url))
  {
    using (SPWeb web = siteCollection.OpenWeb())
    {
      PublishingWeb publishingWeb = PublishingWeb.GetPublishingWeb(web);
      SPListItem pageListItem = ublishingWeb.PagesList.ItemsSPContext.Current.File.UniqueId];
      PublishingPage currentPage = PublishingPage.GetPublishingPage(pageListItem);
      PageLayout currentPageLayout = currentPage.Layout;
      currentPageLayoutName = currentPageLayout.Name;
    }
  }
});

The example above is obviously a very specific case in which we needed the name of the PageLayout used by the current Page. The key message here however is to watch out using SPContext (and other high-level SharePoint objects) within an RunWithElevatedPrivileges block while in anonymous context. It’s very likely to run into some differences compared to using the same elevated code in Windows authenication context.