/// <summary>

        /// 执行用户登录操作

        /// </summary>

        /// <param name="config">授权配置信息</param>

        /// <param name="userData">与登录名相关的用户信息</param>

        /// <param name="expiration">登录Cookie的过期时间，单位：分钟，默认120分钟。</param>

        public static void SignIn(IovAuthConfig config, UserInfo userData, int expiration = 120)

        {

            if (config == null)

                throw new ArgumentNullException("config");

            if (userData == null)

                throw new ArgumentNullException("userData");

            if(string.IsNullOrWhiteSpace(config.AppID))

                throw new ArgumentNullException("AppID");

            // 1. 把需要保存的用户数据转成一个字符串。

            string data = null;

            if (userData != null)

                data = JsonHelper.Serialize(userData);

            // 2. 创建一个FormsAuthenticationTicket，它包含登录名以及额外的用户数据。

            FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(

                2, userData.LoginID, DateTime.Now, DateTime.Now.AddDays(1), true, data);

            // 3. 加密Ticket，变成一个加密的字符串。

            string cookieValue = FormsAuthentication.Encrypt(ticket);

            // 4. 根据加密结果创建登录Cookie

            HttpCookie cookie = new HttpCookie(config.AppID, cookieValue);

            cookie.HttpOnly = true;

            cookie.Secure = FormsAuthentication.RequireSSL;

            cookie.Domain = FormsAuthentication.CookieDomain;

            cookie.Path = FormsAuthentication.FormsCookiePath;

            //if (expiration > 0)

            //默认过期时间：120分钟

            cookie.Expires = DateTime.Now.AddMinutes(expiration == 0 ? 120 : expiration);

            HttpContext context = HttpContext.Current;

            if (context == null)

                throw new InvalidOperationException();

            // 5. 写登录Cookie

            context.Response.Cookies.Remove(cookie.Name);

            context.Response.Cookies.Add(cookie);

        }

  <system.web>

     <authentication mode="Forms">

      <forms name="IOV.Test" loginUrl="/" protection="All" timeout="43200" path="/" domain="" requireSSL="false" slidingExpiration="true" />

    </authentication>

    <compilation debug="true" targetFramework="4.5" />

    <httpRuntime targetFramework="4.5" />

  </system.web>

  <system.webServer>

    <modules runAllManagedModulesForAllRequests="true"></modules>

  </system.webServer>

        /// <summary>

        /// 获取当前用户信息

        /// </summary>

        /// <param name="context">当前Http请求上下文</param>

        /// <returns></returns>

        public static UserInfo TryGetUserInfo(HttpContext context)

        {

            if (context == null)

                throw new ArgumentNullException("context");

            // 1. 读登录Cookie

            HttpCookie cookie = context.Request.Cookies[FormsAuthentication.FormsCookieName];

            if (cookie == null || string.IsNullOrEmpty(cookie.Value))

                return null;

            try

            {

                UserInfo userData = null;

                // 2. 解密Cookie值，获取FormsAuthenticationTicket对象

                FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(cookie.Value);

                if (ticket != null && string.IsNullOrEmpty(ticket.UserData) == false)

                    // 3. 还原用户数据

                    userData = JsonHelper.Desrialize<UserInfo>(ticket.UserData);

                return userData;

            }

            catch { /* 有异常也不要抛出，防止攻击者试探。 */ }

            return null;

        }