跨站点的单点登录

1、Web.config里设置Form登录，name为Cookie名，关键在于domain和loginUrl。把几个要单点登录的站点做同样设置。

   <authentication mode="Forms">
    <forms name="rkanr_validuser" domain=".rkr.com"   loginUrl="http://user.rkr.com/SignIn.aspx"/>
   </authentication>

2、写默认转跳的方法。

         /**//// <summary>
         /// 返回原先登陆页面地址
         /// </summary>
         /// <returns></returns>
         public static string GetLoginUrl()
         {
             return "http://" + WebHelper.Domain.UserDomain + "/SignIn.aspx?ReturnUrl=" + System.Web.HttpContext.Current.Server.UrlEncode(GetUrl());
         }

         /**//// <summary>
         /// 直接跳转向页面
         /// </summary>
         public static void RedirectLoginPage()
         {
             System.Web.HttpContext.Current.Response.Redirect(GetLoginUrl());
         }

3、点击登录或注销时调用上面的方法，页头如果要判断是否登录也一样

     protected void btnLogin_Click(object sender, EventArgs e)
     {
         if (Profile.IsAnonymous)
         {
             WebHelper.Pages.RequestInfo.RedirectLoginPage();
         }
         else
         {
             FormsAuthentication.SignOut();
             Response.Redirect(Session["CurrUrl"].ToString());
         }
     }

注意上面注销的时候要转跳，其实转跳的地方就是本页面，因为注销要刷新才看到效果，不得已而为之

    protected void Page_Load(object sender, EventArgs e)
     {
         if (!IsPostBack)
         {
             Session["CurrUrl"] = WebHelper.Pages.RequestInfo.GetUrl();
        }
     }

4、登录页面显示时保存要转跳的地址

     private void Page_Load(object sender, EventArgs e)
     {
         //自动转跳，start
         if (this.Request.QueryString["ReturnUrl"] != null)
         {
             string ReturnUrl = WebHelper.Pages.RequestInfo.GetQueryString("ReturnUrl");
             Session["ReturnUrl"] = ReturnUrl;
         }
         //自动转跳，end
     }

5、点击登录时，如成功就转跳回要返回的地址

     /**//// <summary>
     /// 登陆
      /// </summary>
     /// <param name="sender"></param>
     /// <param name="e"></param>
     protected void btnLogin_Click(object sender, EventArgs e)
     {
         //收集数据
         string strUserName = this.txtUserName.Text.Trim();
         string strPsw = this.txtPsw.Text.Trim();
         string strValidTime = rbtnValidTime.SelectedItem.Text;

         if (Membership.ValidateUser(strUserName, strPsw))
         {
             setValidTime(strValidTime, strUserName);

             //测试返回地址是否存在，start
             if (Session["ReturnUrl"] != null)
             {
                 Response.Redirect(Session["ReturnUrl"].ToString());
             }
             //测试返回地址是否存在，end
         }
         else
         {
             lblTipInfo.Text = "登陆失败，请重新输入！";
         }
     }


     /**//// <summary>
     /// 设置有效时间，注释的部分原本是要的，但要跨站点登录就不需要了
     /// 而是在上面的方法中转跳，因为系统的转跳只到本站点
     /// </summary>
     /// <param name="strValid"></param>
     protected void setValidTime(string strValid, string strUserName)
     {
         string encTicket;
         FormsAuthenticationTicket ticketObj;

         switch (strValid)
         {
             case "永远":
                 ticketObj = new FormsAuthenticationTicket(strUserName, true, 86400);
                 encTicket = FormsAuthentication.Encrypt(ticketObj);
                 Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, encTicket));
                 //FormsAuthentication.RedirectFromLoginPage(strUserName, true);
                 FormsAuthentication.SetAuthCookie(strUserName, true);
                 break;
             case "一个月":
                 ticketObj = new FormsAuthenticationTicket(strUserName, true, 43200);
                 encTicket = FormsAuthentication.Encrypt(ticketObj);
                 Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, encTicket));
                 //FormsAuthentication.RedirectFromLoginPage(strUserName, true);
                 FormsAuthentication.SetAuthCookie(strUserName, true);
                 break;
             case "一天":
                 ticketObj = new FormsAuthenticationTicket(strUserName, true, 1440);
                 encTicket = FormsAuthentication.Encrypt(ticketObj);
                 Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, encTicket));
                 //FormsAuthentication.RedirectFromLoginPage(strUserName, true);
                 FormsAuthentication.SetAuthCookie(strUserName, true);
                 break;
             case "一小时":
                 ticketObj = new FormsAuthenticationTicket(strUserName, true, 60);
                 encTicket = FormsAuthentication.Encrypt(ticketObj);
                 Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, encTicket));
                 FormsAuthentication.SetAuthCookie(strUserName, true);
                 //FormsAuthentication.RedirectFromLoginPage(strUserName, true);
                 break;
             //浏览器进程
             default:
                 //FormsAuthentication.RedirectFromLoginPage(strUserName, false);
                 FormsAuthentication.SetAuthCookie(strUserName, true);
                 break;
         }
     }