Question

我有一个要求在我的应用程序中添加Facebook登录按钮，用户可以通过Facebook凭据进行身份验证。

我用Google搜索了许多链接，但我发现的是

https://docs.microsoft.com/en-us/aspnet/mvc/overview/security/create-an-aspnet-mvc-5-app-with-facebook-and-google-oauth2-and-openid-sign-on

我的要求是，在我的登录页面添加一个facebook按钮，而不是MVC提供的默认登录页面。

我找到了一个有用的东西，但它抛出异常 PFB我所指的代码

public class AccountController : Controller
    {
        private Uri RedirectUri
        {
            get
            {
                var uriBuilder = new UriBuilder(Request.Url);
                uriBuilder.Query = null;
                uriBuilder.Fragment = null;
                uriBuilder.Path = Url.Action("FacebookCallback");
                return uriBuilder.Uri;
            }
        }

        [AllowAnonymous]
        public ActionResult login()
        {
            return View();
        }

        public ActionResult logout()
        {
            FormsAuthentication.SignOut();
            return View("Login");
        }

        [AllowAnonymous]
        public ActionResult Facebook()
        {
            var fb = new FacebookClient();
            var loginUrl = fb.GetLoginUrl(new
            {
                client_id = "444195149059600",
                client_secret = "89223ca2d87cc4a741000d5c1ea57694",
                redirect_uri = RedirectUri.AbsoluteUri,
                response_type = "code",
                scope = "email" // Add other permissions as needed
            });

            return Redirect(loginUrl.AbsoluteUri);
        }

        public ActionResult FacebookCallback(string code)
        {
            var fb = new FacebookClient();
            dynamic result = fb.Post("oauth/access_token", new
            {
                client_id = "444195149059600",
                client_secret = "89223ca2d87cc4a741000d5c1ea57694",
                redirect_uri = RedirectUri.AbsoluteUri,
                code = code
            });

            var accessToken = result.access_token;

            // Store the access token in the session for farther use
            Session["AccessToken"] = accessToken;

            // update the facebook client with the access token so 
            // we can make requests on behalf of the user
            fb.AccessToken = accessToken;

            // Get the user's information
            dynamic me = fb.Get("me?fields=first_name,middle_name,last_name,id,email");
            string email = me.email;
            string firstname = me.first_name;
            string middlename = me.middle_name;
            string lastname = me.last_name;

            // Set the auth cookie
            FormsAuthentication.SetAuthCookie(email, false);
            return RedirectToAction("Index", "Home");
        }
    }
}

我在Actionresult Facebook（）中遇到一些错误，我无法解决它。你能指导一下吗？先谢谢

Answer 1

您的链接是指MVC 5，如果您使用MVC 4，请查看此处：https://docs.microsoft.com/en-us/aspnet/mvc/overview/older-versions/using-oauth-providers-with-mvc

这些版本之间存在一些重要的差异。如果您提供有关收到的错误的更多信息，则更容易对基本问题给出具体提示

Bst rgrds

Answer 2

在你看来，你必须有这样的感觉;

using (Html.BeginForm("ExternalLogin", "Account", new {Model.ReturnUrl}))
        {
            @Html.AntiForgeryToken()
            <div id="socialLoginList">
                <p>
                    @foreach (var p in loginProviders)
                    {
                        <button type="submit" class="btn btn-default" id="@p.AuthenticationType" name="provider" value="@p.AuthenticationType" title="Log in using your @p.Caption account">@p.AuthenticationType</button>
                    }
                </p>
            </div>
        }

我假设您将OWIN安装到您的应用程序中。所以在你的初创班上

      public partial class Startup
            {

                public static IDataProtectionProvider DataProtectionProvider { get; set; }       
                public void ConfigureAuth(IAppBuilder app)
                {
         app.UseFacebookAuthentication(
                       appId: "",
                       appSecret: "");
}
    }

在外部登录时，您有这样的方法

 [AllowAnonymous]
            public async Task<ActionResult> VerifyCode(string provider, string returnUrl, bool rememberMe)
            {
                // Require that the user has already logged in via username/password or external login
                if (!await SignInManager.HasBeenVerifiedAsync())
                    return View("Error");
                return View(new VerifyCodeViewModel { Provider = provider, ReturnUrl = returnUrl, RememberMe = rememberMe });
            }

[AllowAnonymous]
        public async Task<ActionResult> ExternalLoginCallback(string returnUrl)
        {
            var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();
            if (loginInfo == null)
                return RedirectToAction("Login");

            // Sign in the user with this external login provider if the user already has a login
            var result = await SignInManager.ExternalSignInAsync(loginInfo, false);
            switch (result)
            {
                case SignInStatus.Success:
                    return RedirectToLocal(returnUrl);
                case SignInStatus.LockedOut:
                    return View("Lockout");
                case SignInStatus.RequiresVerification:
                    return RedirectToAction("SendCode", new { ReturnUrl = returnUrl, RememberMe = false });
                case SignInStatus.Failure:
                default:
                    // If the user does not have an account, then prompt the user to create an account
                    ViewBag.ReturnUrl = returnUrl;
                    ViewBag.LoginProvider = loginInfo.Login.LoginProvider;
                    return View("ExternalLoginConfirmation",
                        new ExternalLoginConfirmationViewModel { Email = loginInfo.Email });
            }
        }

    //
    // POST: /Account/ExternalLoginConfirmation
    [HttpPost]
    [AllowAnonymous]
    [ValidateAntiForgeryToken]
    public async Task<ActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model,
        string returnUrl)
    {
        if (User.Identity.IsAuthenticated)
            return RedirectToAction("Index", "Manage");

        if (ModelState.IsValid)
        {
            // Get the information about the user from the external login provider
            var info = await AuthenticationManager.GetExternalLoginInfoAsync();
            if (info == null)
                return View("ExternalLoginFailure");
            var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
            var result = await UserManager.CreateAsync(user);
            if (result.Succeeded)
            {
                result = await UserManager.AddLoginAsync(user.Id, info.Login);
                if (result.Succeeded)
                {
                    await SignInManager.SignInAsync(user, false, false);
                    return RedirectToLocal(returnUrl);
                }
            }
            AddErrors(result);
        }

        ViewBag.ReturnUrl = returnUrl;
        return View(model);
    }

在c＃mvc4的登录页面中添加Facebook登录按钮

2 个答案: