Facebook 注销 Windows Phone 应用程序而不打开 WebBrowser

Question

我正在尝试使用 Facebook 登录和注销操作开发 Windows Phone 7 应用程序。我通过打开 WebBrowser 找到了 Facebook SDK 并使用它来执行登录。用户在此浏览器中输入凭据并成功登录。此外，我设法在不使用任何 SDK 的情况下登录用户，只使用 http 请求，就像 SDK 实际所做的那样。但是，我想在不使用任何 WebBrowser 的情况下注销用户，而只需单击一个按钮。网络上有很多解决方案建议我打开网络浏览器并将其导航到某个 URL 以注销。然而，这不是我想要的。我认为应该有一种方法可以通过清除 cookie 来注销，我不完全知道该怎么做，或者您建议的任何其他方法。我的部分代码如下：

    private static String appID = "";
    private static String appSecret = "";

    public static void login(String[] permissions)
    {
        try
        {
            permissionArray = permissions;

            popup = new Popup();
            popup.Height = 480;
            popup.Width = 480;
            popup.VerticalOffset = 100;
            FacebookLoginUserControl control = new FacebookLoginUserControl();
            control.facebookWebBrowser.Loaded += new RoutedEventHandler(webBrowser_Loaded);
            control.facebookWebBrowser.Navigated += new EventHandler<System.Windows.Navigation.NavigationEventArgs>(webBrowser_Navigated);

            popup.Child = control;
            popup.IsOpen = true;
        }
        catch (Exception e)
        {
            //handle
        }
    }

    private static void webBrowser_Loaded(Object sender, RoutedEventArgs e)
    {
        WebBrowser wb = (WebBrowser)sender;
        String loginUrl = GetFacebookLoginUrl();
        wb.Navigate(new Uri(loginUrl));
    }

    private static String GetFacebookLoginUrl()
    {
        String permissionString = String.Empty;
        if (permissionArray.Length > 0)
            permissionString = String.Join(",", permissionArray);

        var uriParams = new Dictionary<string, string>() {
                    {"client_id", appID},
                    {"response_type", "token"},
                    {"scope", permissionString},
                    {"redirect_uri", "http://www.facebook.com/connect/login_success.html"},
                    {"display", "touch"}
                };
        StringBuilder urlBuilder = new StringBuilder();
        foreach (var current in uriParams)
        {
            if (urlBuilder.Length > 0)
            {
                urlBuilder.Append("&");
            }
            var encoded = HttpUtility.UrlEncode(current.Value);
            urlBuilder.AppendFormat("{0}={1}", current.Key, encoded);
        }
        var loginUrl = "http://www.facebook.com/dialog/oauth?" + urlBuilder.ToString();

        return loginUrl;
    }

    private static void webBrowser_Navigated(Object sender, System.Windows.Navigation.NavigationEventArgs e)
    {
        if (string.IsNullOrEmpty(e.Uri.Fragment)) return;
        if (e.Uri.AbsoluteUri.Replace(e.Uri.Fragment, "") == "http://www.facebook.com/connect/login_success.html")
        {
            string text = HttpUtility.HtmlDecode(e.Uri.Fragment).TrimStart('#');
            var pairs = text.Split('&');
            foreach (var pair in pairs)
            {
                var kvp = pair.Split('=');
                if (kvp.Length == 2)
                {
                    if (kvp[0] == "access_token")
                    {
                        accessToken = kvp[1];
                        MessageBox.Show("Access granted");
                        RequestUserProfile();
                    }
                }
            }
            if (string.IsNullOrEmpty(accessToken))
            {
                MessageBox.Show("Unable to authenticate");
            }
            popup.IsOpen = false;
        }
    }

    private static void RequestUserProfile()
    {
        var profileUrl = string.Format("https://graph.facebook.com/me?access_token={0}", HttpUtility.UrlEncode(accessToken));
        request = (HttpWebRequest)HttpWebRequest.Create(new Uri(profileUrl));
        request.Method = "GET";
        request.BeginGetResponse(result =>
        {
            try
            {
                var resp = (result.AsyncState as HttpWebRequest).EndGetResponse(result);
                using (var strm = resp.GetResponseStream())
                {
                    StreamReader sr = new StreamReader(strm);
                    var responseString = sr.ReadToEnd();

                }
            }
            catch (Exception ex)
            {
                //
            }
        }, request);
    }

解决问题的任何想法。 提前致谢

Answer 1

使用 webBrowser 到底有什么可怕的？如果您以编程方式创建 WebBrowser 对象，它将不可见，除非您将其添加到表单/页面的某个位置。如果你想清除 Facebook 的 cookie，解决方案是这样的：

// Can be invoked from your button_click event
 public void TryLogout()
        {
            webBrowser = new WebBrowser();

            Uri uri = new Uri("http://m.facebook.com/home.php?r", UriKind.Absolute);
            webBrowser.LoadCompleted += new LoadCompletedEventHandler(webBrowser_TryLogoutLoadCompleted);
            webBrowser.Navigate(uri);
        } 

然后：

private void webBrowser_TryLogoutLoadCompleted(object sender, EventArgs e)
        {
            try
            {
                var cookies = webBrowser.GetCookies();

                foreach (Cookie cookie in cookies)
                {
                    if (cookie.Domain.Contains("m.facebook.com"))
                    {
                        cookie.Discard = true;
                        cookie.Expired = true;
                    }
                }
            // we've just cleaned up cookies

            }
            finally
            {
                webBrowser.LoadCompleted -= webBrowser_TryLogoutLoadCompleted;
            }
        }

希望这会有所帮助。

GetCookies method