public ActionResult Login(LoginUserModel model, string ReturnUrl)
        {
            Users_BLL bll = new Users_BLL();

            if (bll.CheckExist(model.UserName, model.PassWord))
            {
                FormsAuthentication.SetAuthCookie(model.UserName, false);
                //if (((Url.IsLocalUrl(returnUrl) && (returnUrl.Length > 1))&& (returnUrl.StartsWith("/") && !returnUrl.StartsWith("//"))) && !returnUrl.StartsWith(@"/\"))
                if (!string.IsNullOrEmpty(ReturnUrl))
                {
                    return(Redirect(ReturnUrl));
                }
                else
                {
                    //return RedirectToAction("Index", "Home");
                    string url = Url.Content(Request.UrlReferrer.AbsoluteUri);


                    string action = url.Substring(url.LastIndexOf("/") + 1, url.Length - url.LastIndexOf("/") - 1);
                    if (action == "Login" || action == "login")
                    {
                        return(RedirectToAction("Index", "Home"));
                    }
                    else
                    {
                        return(Redirect(Url.Content(Request.UrlReferrer.AbsoluteUri)));
                    }
                }
                //  return RedirectToAction("Index", "Home");
            }
            ModelState.AddModelError("", "用户名或密码错误,请重新输入!");
            return(View(model));
        }
        public ActionResult CheckUser(string UserName)
        {
            Users_BLL bll = new Users_BLL();

            if (bll.CheckExist(UserName))
            {
                bool result = false;
                return(Json(result, JsonRequestBehavior.AllowGet));
            }
            else
            {
                bool result = true;
                return(Json(result, JsonRequestBehavior.AllowGet));
            }
        }