Jquery ajax json 值回传不了

 function Login() {
            if (CheckLogin()) {
                $.ajax({
                    url: "@Url.Action("Login", "Login")",
                    type: "post",
                    dataType: "json",
                    data: "UserName=" + $("#UserName").val() + "&PassWord=" + $("#PassWord").val() + "&Yzm=" + $("#Yzm").val(),
                    success: function (data) {
                        data = eval("(" + data + ")");
                        if (data.result == 0) {
                            EFSPrompt.show({ content: ‘验证码不正确‘ });
                        }
                        else if (data.result == 1)
                            window.location.href = "@Url.Action("Index", "Home")";
                        else if (data.result == 2)
                            EFSPrompt.show({ content: ‘用户名或密码错误‘ });
                        else if (data.result == 3)
                            window.location.href = "@Url.Action("ReSetPwd")?para=first";
                    },
                    error: function (e, b) {
                        alert("error");
                    }
                });

            }
        }

controller 中的方法： 

[HttpPost]
        public JsonResult Login(FormCollection collection)
        {
            string UserName = SecurityRequst("UserName");
            string Password = SecurityRequst("PassWord");
            string Yzm = SecurityRequst("Yzm");
            HttpCookie YZMCookie = Request.Cookies["YZMCookie"];
            string RealYzm = YZMCookie == null ? "" : YZMCookie["yzm"];//真实的验证码

            //if (Yzm != RealYzm || YZMCookie == null)
            //    return Json("{\"result\":0}");

            if (_StudentBaseInfoBO.ValidataUser(UserName, Password))
            {
                //写日志
                AddLoginLog(UserName);
                //if (Password =="123456")//说明是还没改密码
                //{
                //    Session[AppConfig.ResetUserPWDKey] = UserName;
                //    return Json("{\"result\":3}");
                //}
                //else
                //{
                 return Json("{\"result\":1}");
               
                //}
            }
            else
                return Json("{\"result\":2}");
        }