HttpContext.Current.User.Identity.IsAuthenticated=false;

HttpContext.Current.User.Identity.Name==""

解釋：當(dāng)用戶登錄時(shí)，服務(wù)器為確認(rèn)客戶端通過(guò)驗(yàn)證要通過(guò)cookie向客戶端寫驗(yàn)證（Authenticat）信息,在登錄頁(yè)面剛驗(yàn)證完成后服務(wù)器 還沒有把cookie 回發(fā)到Client，所以會(huì)沒有值，當(dāng)服務(wù)器第二次Response的時(shí)候，就會(huì)從客戶端讀取Cookie，要想有此Cookie還要在 web.config文件中配置相應(yīng)的參數(shù)

<system.web>
    <authentication mode="Forms">
      <forms domain="bokoAdmin" timeout="20" loginUrl="Login.aspx" path="/"></forms>
    </authentication>

   <authorization>
      <allow users="*"/>
    </authorization>

<system.web>

程序驗(yàn)證：

            if (Membership.ValidateUser(tbx_username.Text.TrimEnd(), tbx_password.Text.TrimEnd()))
            {
               
                FormsAuthentication.SetAuthCookie(tbx_username.Text.TrimEnd(), true,FormsAuthentication.FormsCookiePath);
                FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(
    1, tbx_username.Text, DateTime.Now, DateTime.Now.AddMinutes(20), false, tbx_username.Text);
                // generate new identity
                FormsIdentity identity = new FormsIdentity(ticket);
                HttpCookie cookie = new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(ticket));
                // write to client.
                Response.Cookies.Add(cookie);
                }

其中加粗體為主要語(yǔ)句，有此一句就可以實(shí)現(xiàn)HttpContext.Current.User.Identity.IsAuthenticated=true;