public ActionResult Register()
        {
            if (Session["userid"] != null)
            {
                ViewBag.Error = "你已经登陆";
                return RedirectToAction("Index", "Home");
            }
            else
            {
                return View();
            }

        }
        [HttpPost]
        public ActionResult Register(FormCollection RegUser)
        {
            var model = new Blog.Models.User()
            {
                UserName = RegUser["UserName"].ToLower().Trim(),
                Email = RegUser["Email"].ToLower().Trim(),
                Password = RegUser["Password"].toMD5(),
                QQ = RegUser["QQ"].Trim(),
                RegTime = DateTime.Now,
                LastLoginTime = DateTime.Now,
                RegIP = Request.UserHostAddress,
                LastLoginIP = Request.UserHostAddress,
                RoleID = 1
            };
            var dal = new BlogEnt();
            dal.Users.Add(model);
            dal.SaveChanges();
            int id = model.UserID;
            Session["userid"] = id;
            return RedirectToAction("Index", "Home");
        }

        #endregion

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
        <h2>注册用户</h2>

        <div class="editor-label">
            @Html.LabelFor(model => model.UserName)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.UserName)<span>*必填.用于在网站中显示名称</span>
            @Html.ValidationMessageFor(model => model.UserName)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.Email)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Email)<span>*用于登陆网站和找回密码</span>
            @Html.ValidationMessageFor(model => model.Email)
        </div>   
    
        <div class="editor-label">
            @Html.LabelFor(model => model.Password)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Password)<span>*</span>
            @Html.ValidationMessageFor(model => model.Password)
        </div>

        <p>
            <input type="submit" value="提交注册" />
        </p>
}

var model = new Blog.Models.User();
model.UserName=...