MVC Ajax.BeginForm 实例

 <script src="~/Scripts/jquery-1.8.2.min.js"></script>
 <script src="~/Scripts/jquery.unobtrusive-ajax.min.js"></script>

 //指定提交到Home控制器下的Login方法
//HttpMethod  指定提交方式为Post
//OnSuccess 返回方法为AfterAdd
//id id名称为frmSet
//type="submit" 按钮类型为 submit
@using (Ajax.BeginForm("Login","Home", new { }, new AjaxOptions() { HttpMethod = "Post", OnSuccess = "AfterAdd" }, new { id = "frmSet" }))
        {
        <div class="loginbox">
            <ul>
                <li>
<input name="username" type="text" class="loginuser" value="admin" alt="admin" title="用户名" onclick="JavaScript:this.value=‘‘"/>
</li>
                <li>
<input name="pwd" type="text" class="loginpwd" value="密码" alt="密码" title="密码" onclick="JavaScript: this.type = ‘password‘;this.value=‘‘" />
</li>
                <li>
<input name="CheckCode" type="text" class="logincode" value="验证码" alt="验证码" title="验证码" onclick="JavaScript:this.value=‘‘" />
<img src="/Cms/Home/GetCodeImage" style="width: 100px; height:30px;" id="CodeImage" alt="See? Another one"
 onclick="this.src=‘/Cms/Home/GetCodeImage?GUID=‘+ new Date().getTime();">
</li>
                <li>
<input name="" type="submit" class="loginbtn" value="登录"  /></li>
            </ul>
        </div>
            }

        [HttpPost]
        public ActionResult Login(FormCollection form)
        {
            string msg = "";
            string usernmae = Common.Tool.GetSafeSqlandHtml(Request ["username"]);
            string pwd = Common.Tool.GetSafeSqlandHtml(Request["pwd"]);
            string checkCode = Common.Tool.GetSafeSqlandHtml(Request["CheckCode"]);
            if (Session["ValidataCode"] == null || checkCode != Session["ValidataCode"].ToString())
            {
                return Json(new { isok = "erro", msg = "验证码错误" });
            }
            if (string.IsNullOrEmpty(usernmae) || string.IsNullOrEmpty(pwd))
            {
                return Json(new { isok = "erro", msg = "用户名或密码不能为空" });
            }
            pwd = Common.Tool.Md5(pwd).ToUpper();
            MODEL.User us = BLL.User.SelectModel("userName=‘" + usernmae + "‘ and PassWord=‘" + pwd + "‘ ");
            if (us == null)
            {
                msg = "用户名或密码错误";
            }
            else
            {
                if (us.Status == 1)
                {
                    return Json(new { isok = "erro", msg = "该管理员已被禁用" });
                }
                else
                { 
                    MODEL.LoginLog ulogin = new MODEL.LoginLog();
                    ulogin.Uid = us.Id;
                    ulogin.UserID = us.UserName;
                    ulogin.UserName = us.Name ;
                    ulogin .IP  = Common .Tool .GetClientIp ();
                    System.Web.HttpContext Current = System.Web.HttpContext.Current;
                    ulogin.LoginWeb = Current.Request.ServerVariables["HTTP_USER_AGENT"];
                    ulogin.AddTime = DateTime.Now;
                    BLL.LoginLog.Add(ulogin);
                    Current.Session["User"] = us;
                    string goUrl = "/Cms/Default/Index";
                    return Json(new { isok = "ok", gourl = goUrl });
                }
            }
            return Json(new { isok = "erro", msg = msg });

        }

<script language="javascript">      
        function AfterAdd(result) {
            if (result.isok == "ok") {
                alert("登录成功！");
                window.location=result.gourl;
            }
            else {
                alert(result.msg);
                //window.location.reload();
            }
        }
    </script>