Fix due to the modified WebSocketServer.cs

Example2/Program.cs

@@ -14,7 +14,7 @@ namespace Example2
       wssv.Start();
       Console.WriteLine(
         "WebSocket Server (url: {0})\n  listening on address: {1} port: {2}\n",
-        wssv.Url, wssv.Address, wssv.Port);
+        wssv.Uri, wssv.Address, wssv.Port);
 
       Console.WriteLine("Press any key to stop server...");
       Console.ReadLine();