我的目标是使用FB登录按钮,以便FB用户可以登录我的ASP.NET MVC 3网站。最近Facebook C#SDK的情况似乎发生了变化,所有old examples都不适用于新版本。我已经尝试了一天让他们上班......我正在处理教程Getting Started with the Facebook C# SDK for ASP.NET
目前,当我浏览http://localhost:8033/
时,它似乎会自动登录(即使重新启动Chrome后),因为它显示" my-name 使用我的应用内名称"并显示我的照片。我希望它显示一个FB登录按钮。当我转到http://localhost:8033/Home/About
时,我收到Session["AccessToken"]
为空的错误(这是有道理的,因为它显然没有设置)。
以下是我所拥有的:
HomeController.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Facebook;
namespace FacebookTest.Controllers
{
public class HomeController : Controller
{
public ActionResult Index()
{
ViewBag.Message = "Welcome to ASP.NET MVC!";
return View();
}
public ActionResult About()
{
var accessToken = Session["AccessToken"].ToString();
var client = new FacebookClient(accessToken);
dynamic result = client.Get("me", new { fields = "name,id" });
string name = result.name;
string id = result.id;
ViewBag.Message = "Hello id: " + id;
return View();
}
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult FacebookLogin(HttpContext context)
{
var accessToken = context.Request["accessToken"];
context.Session["AccessToken"] = accessToken;
return RedirectToAction("About");
}
}
}
Index.cshtml
@{
ViewBag.Title = "Home Page";
}
<h2>@ViewBag.Message</h2>
<p>
To learn more about ASP.NET MVC visit <a href="http://asp.net/mvc" title="ASP.NET MVC Website">http://asp.net/mvc</a>.
</p>
<div id="fb-root"></div>
<script>
window.fbAsyncInit = function () {
FB.init({
//appId: 'YOUR_APP_ID', // App ID
appId: '<MY-NUMBER-REMOVED>', // App ID
status: true, // check login status
cookie: true, // enable cookies to allow the server to access the session
xfbml: true // parse XFBML
});
// Additional initialization code here
FB.Event.subscribe('auth.authResponseChange', function (response) {
if (response.status === 'connected') {
// the user is logged in and has authenticated your
// app, and response.authResponse supplies
// the user's ID, a valid access token, a signed
// request, and the time the access token
// and signed request each expire
var uid = response.authResponse.userID;
var accessToken = response.authResponse.accessToken;
// TODO: Handle the access token
// Do a post to the server to finish the logon
// This is a form post since we don't want to use AJAX
var form = document.createElement("form");
form.setAttribute("method", 'post');
//form.setAttribute("action", '/FacebookLogin.ashx');
form.setAttribute("action", '/Home/FacebookLogin');
var field = document.createElement("input");
field.setAttribute("type", "hidden");
field.setAttribute("name", 'accessToken');
field.setAttribute("value", accessToken);
form.appendChild(field);
document.body.appendChild(form);
form.submit();
} else if (response.status === 'not_authorized') {
// the user is logged in to Facebook,
// but has not authenticated your app
} else {
// the user isn't logged in to Facebook.
}
});
};
// Load the SDK Asynchronously
(function (d) {
var js, id = 'facebook-jssdk', ref = d.getElementsByTagName('script')[0];
if (d.getElementById(id)) { return; }
js = d.createElement('script'); js.id = id; js.async = true;
js.src = "//connect.facebook.net/en_US/all.js";
ref.parentNode.insertBefore(js, ref);
} (document));
</script>
<div class="fb-login-button" data-show-faces="true" data-width="400" data-max-rows="1"></div>
About.cshtml
@{
ViewBag.Title = "About Us";
}
<h2>About</h2>
<p>
@ViewBag.Message
</p>
你能告诉我如何解决这个问题,以便显示一个FB登录按钮,点击它时会要求用户进行FB身份验证,发送回来,然后我的应用会将他们识别为登录用户吗? / p>
答案 0 :(得分:3)
对于“登录”按钮,如果您在访问应用程序之前登录到Facebook,则会看到面部而不是登录按钮,获取“登录”按钮的唯一方法是转到facebook.com并注销或使用C#SDK进行facebook注销。根据您的要求,这可能是也可能不是您想要的。如果这是您真正想要的,那么SDK文档中会有一些Re-Authentication。
我通过删除submit()来调整你的应用程序,并用ajax帖子替换它,FacebookLogin操作被更改了,我在About操作上添加了一些错误处理。您的原始应用程序将起作用,但如果您已登录Facebook,它将自动重定向到“关于”。
更新添加了一个不使用Javascript的登录链接,插入appid和appsecret并相应地调整portnumber。这是根据找到的here服务器端登录样本改编的,它比这段代码更漂亮:)
注意在服务器端流中传递的状态值应该是您应该在ConnectResponse()方法中验证的unqiue值,即在FacebookLoginNoJs中生成一个值并确保它在ConnectResponse可防止跨网站请求forgery
<强> HomeController.cs 强>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Facebook;
namespace FacebookTest.Controllers
{
public class HomeController : Controller
{
public ActionResult Index()
{
ViewBag.Message = "Welcome to ASP.NET MVC!";
return View();
}
public ActionResult About()
{
ViewBag.Message = "Please log in first";
if (Session["AccessToken"] != null)
{
var accessToken = Session["AccessToken"].ToString();
var client = new FacebookClient(accessToken);
try
{
dynamic result = client.Get("me", new { fields = "name,id" });
string name = result.name;
string id = result.id;
ViewBag.Message = "Hello id: " + id + " aka " + name;
}
catch (FacebookOAuthException x)
{
}
}
return View();
}
public void FacebookLogin(string uid, string accessToken)
{
var context = this.HttpContext;
context.Session["AccessToken"] = accessToken;
}
public ActionResult FacebookLoginNoJs()
{
return Redirect("https://www.facebook.com/dialog/oauth?client_id=MY-APPID-REMOVED&redirect_uri=http://localhost:45400/Home/ConnectResponse&state=secret");
}
public ActionResult ConnectResponse(string state, string code, string error, string error_reason, string error_description, string access_token, string expires)
{
if (string.IsNullOrEmpty(error))
{
try
{
var client = new FacebookClient();
dynamic result = client.Post("oauth/access_token",
new
{
client_id = "MY-APPID-REMOVED",
client_secret = "MY-APP-SECRET-REMOVED",
redirect_uri = "http://localhost:45400/Home/ConnectResponse",
code = code
});
Session["AccessToken"] = result.access_token;
if (result.ContainsKey("expires"))
Session["ExpiresIn"] = DateTime.Now.AddSeconds(result.expires);
}
catch
{
// handle errors
}
}
else
{
// Declined, check error
}
return RedirectToAction("Index");
}
}
}
<强> Index.cshtml 强>
@{
ViewBag.Title = "Home Page";
}
<h2>@ViewBag.Message</h2>
<p>
To learn more about ASP.NET MVC visit <a href="http://asp.net/mvc" title="ASP.NET MVC Website">http://asp.net/mvc</a>.
</p>
<div id="fb-root"></div>
<script>
window.fbAsyncInit = function () {
FB.init({
//appId: 'YOUR_APP_ID', // App ID
appId: 'MY-APPID-REMOVED', // App ID
status: true, // check login status
cookie: true, // enable cookies to allow the server to access the session
xfbml: true // parse XFBML
});
// Additional initialization code here
FB.Event.subscribe('auth.authResponseChange', function (response) {
if (response.status === 'connected') {
var uid = response.authResponse.userID;
var accessToken = response.authResponse.accessToken;
var url = '/Home/FacebookLogin';
$.post(url, { uid: uid, accessToken: accessToken }, function (data) {
});
} else if (response.status === 'not_authorized') {
// the user is logged in to Facebook,
// but has not authenticated your app
} else {
// the user isn't logged in to Facebook.
}
});
};
// Load the SDK Asynchronously
(function (d) {
var js, id = 'facebook-jssdk', ref = d.getElementsByTagName('script')[0];
if (d.getElementById(id)) { return; }
js = d.createElement('script'); js.id = id; js.async = true;
js.src = "//connect.facebook.net/en_US/all.js";
ref.parentNode.insertBefore(js, ref);
} (document));
</script>
<div class="fb-login-button" data-show-faces="true" data-width="400" data-max-rows="1"></div>
@Html.ActionLink("The NoJs Login", "FacebookLoginNoJs", "Home")
<强> About.cshtml 强>
@{
ViewBag.Title = "About Us";
}
<h2>About</h2>
<p>
@ViewBag.Message
</p>