Facebook.FacebookOAuthClient.GetLoginUrl C# (CSharp) Method

        public Uri GetLoginUrl()
        {
            return GetLoginUrl(null);
        }

        /// <summary>
        /// Get FacebookOAuthClient.
        /// </summary>
        void MainPage_Loaded()
        {
            using (DbStorage fbdb = new DbStorage(strConnectionString))
            {
                IQueryable<Db> fbQuery = from db in fbdb.user select db;
                Db ac = fbQuery.FirstOrDefault();
                if(ac == null){
                    string appId = "YOUR FACEBOOK APP ID";
                    string[] extendedPermissions = new[] { "publish_stream"};

                    var oauth = new FacebookOAuthClient { AppId = appId };
                    var parameters = new Dictionary<string, object>
                            {
                               { "response_type", "token" },
                                { "display", "touch" }
                            };
                    if (extendedPermissions != null && extendedPermissions.Length > 0)
                    {
                        var scope = new StringBuilder();
                        scope.Append(string.Join(",", extendedPermissions));
                        parameters["scope"] = scope.ToString();
                    }
                    var loginUrl = oauth.GetLoginUrl(parameters);
                    //Add webBrowser to the contentPanel
                    _webBrowser.Navigate(loginUrl);
                    ContentPanel.Children.Add(_webBrowser);
                    _webBrowser.Navigated += webBrowser_Navigated;
                    //Open the facebook login page into the browser
           
            }
        }
        }