Wie, um alle Arbeitsaufgaben von tfs via c#

Guten Tag!

Ich versuche alle WorkItems aus Sammlung bei TFS (2010).
Ich fand blog mit einigen code-Beispiel, aber es funktioniert nicht gut:

ICommonStructureService Iss = (ICommonStructureService)projCollection.GetService(typeof(ICommonStructureService));

Diese code-Zeile liefert einen Fehler - keine Verbindung zum TFS (den gleichen code schließt gut).
Ok, ich versuche zu umschreiben, dass dieser code und versuchen, diese (anderen Arbeit Beispiel aus msdn):

private static String _tfsURI ="http:tfsServer:port/tfsUrl"
static void Main(string[] args)
    {
        //Connect to Team Foundation Server
        //    Server is the name of the server that is running the application tier for   Team Foundation.
        //    Port is the port that Team Foundation uses. The default port is 8080.
        //    VDir is the virtual path to the Team Foundation application. The default path is tfs.
        Uri tfsUri = (args.Length < 1) ?
            new Uri(_tfsURI) : new Uri(args[0]);

        TfsConfigurationServer configurationServer =
            TfsConfigurationServerFactory.GetConfigurationServer(tfsUri);

        Console.WriteLine("Get the catalog of team project collections \n");
        //Get the catalog of team project collections
        ReadOnlyCollection<CatalogNode> collectionNodes = configurationServer.CatalogNode.QueryChildren(
            new[] { CatalogResourceTypes.ProjectCollection },
            false, CatalogQueryOptions.None);
        //List the team project collections
        foreach (CatalogNode collectionNode in collectionNodes)
        {
            Console.WriteLine(collectionNode.Resource.DisplayName);

            //Use the InstanceId property to get the team project collection
            Guid collectionId = new Guid(collectionNode.Resource.Properties["InstanceId"]);
            TfsTeamProjectCollection teamProjectCollection = configurationServer.GetTeamProjectCollection(collectionId);


                    ICommonStructureService Iis = (ICommonStructureService)teamProjectCollection.GetService(typeof(ICommonStructureService));
                 ProjectInfo[] projInfo = Iis.ListAllProjects();
              // WorkItemStore wis = (WorkItemStore)teamProjectCollection.GetService();

                 var wis = (WorkItemStore)teamProjectCollection.GetService(typeof(ICommonStructureService));

            foreach (var p in projInfo)
                 {

                     Console.WriteLine("Name:" + p.Name + "Status" + p.Status);
                     var wic = wis.Query(" SELECT [System.Id], [System.WorkItemType]," +
            " [System.State], [System.AssignedTo], [System.Title] " +
              " FROM WorkItems " +
              " WHERE [System.TeamProject] = '" + p.Name +
               "' ORDER BY [System.WorkItemType], [System.Id]");

                     Console.WriteLine("wic.Count:"+wic.Count);

                     foreach (var wi in wic)
                     {

                         Console.WriteLine(wi.Id);
                         Console.WriteLine(wi.Title);
                     }

                 }

            //Print the name of the team project collection
               Console.WriteLine("Collection: " + teamProjectCollection.Name);

            //Get a catalog of team projects for the collection
            ReadOnlyCollection<CatalogNode> projectNodes = collectionNode.QueryChildren(
                new[] { CatalogResourceTypes.TeamProject },
                false, CatalogQueryOptions.None);

            //List the team projects in the collection
            foreach (CatalogNode projectNode in projectNodes)
            {
                Console.WriteLine(" Team Project: " + projectNode.Resource.DisplayName);

            }
        }
        Console.ReadLine();
    }

So, ich bekomme error: cannot cast object-Typ "Microsoft.TeamFoundation.Proxy.CommonStructureService" auf "Microsoft.TeamFoundation.WorkItemTracking.Client.WorkItemStore".

Bitte helfen Sie mir, heiß, um alle Arbeitsaufgaben von Tfs.