Blog.Web.Api.Controllers.AccountController.GetExternalLogins C# (CSharp) Method

        public IEnumerable<ExternalLoginViewModel> GetExternalLogins(string returnUrl, bool generateState = false)
        {
            IEnumerable<AuthenticationDescription> descriptions = Authentication.GetExternalAuthenticationTypes();

            string state;

            if (generateState)
            {
                const int strengthInBits = 256;
                state = RandomOAuthStateGenerator.Generate(strengthInBits);
            }
            else
            {
                state = null;
            }

            return descriptions.Select(description => new ExternalLoginViewModel
            {
                Name = description.Caption,
                Url = Url.Route("ExternalLogin", new
                    {
                        provider = description.AuthenticationType,
                        response_type = "token",
                        client_id = Startup.PublicClientId,
                        redirect_uri = new Uri(Request.RequestUri, returnUrl).AbsoluteUri,
                        state
                    }),
                State = state
            }).ToList();
        }