后台写js

   public ActionResult CheckLogon()
        {
            var con = "document.write('{0}')";
            if (AuthManager.UserWebIdentity == null)
            {
                const string text = "<div class="count_login"><span>欢迎来到路游租车！</span><div class="login"><a href="http://passport.luyou666.com/Account/Logon">登录</a><a class="zhuce" href="http://passport.luyou666.com/Account/VerificationPhoneUser">注册</a></div></div>";
                con = con.FormatValue(text);
            }
            else
            {
                var text = "<div class="count_login"><span><a href="http://my.luyou666.com">" +
                           AuthManager.UserWebIdentity.Profile.LoginId +
                           "<img src="http://passport.luyou666.com/Content/User/icon/name.gif" /></a>欢迎来到路游租车！</span><div class="tuichu"><a href="/logout">退出</a></div></div>";
                con = con.FormatValue(text);
            }
            return Content(con, MimeCollection.Js.ContentType);
        }

前端调用

  <script type="text/javascript" src="http://passport.luyou666.com/Account/CheckLogon"></script>