背景
我有一个基于 MVC 5、EF 6 DB First 和 DevExpress 扩展的不完整项目，具有以下代码规范（所有原始非英语变量名称已更改，整个代码已简化以符合 MCVE）：
模型（命名空间ProjectName.Models：）
public class DBContext : DbContext
{
public DBContext : base("ConnectionStringName")
{
public DbSet<WinnerTable> Winners { get; set; }
public DbSet<UnitTable> Units { get; set; }
public DbSet<CustomerTable> Customers { get; set; }
}
}
[Table("WinnerTable")]
public class WinnerModel : IWinnerRepository
{
public String WinnerID { get; set; }
public String CustomerID { get; set; }
public String CustomerName { get; set; }
public String TranDate { get; set; }
public List<UnitModel> UnitList { get; set; }
public List<UnitModel> GetUnitList(String sessionID, DateTime tranDate)
{
// query to unit list
using (var DB = new DBContext())
{
var query = (from unit in DB.Units
where unit.SessionID == sessionID && unit.TranDate = tranDate
select new UnitModel()
{
// unit table to unit model definition
}).ToList();
return query;
}
}
}
[Table("UnitTable")]
public class UnitModel
{
public String UnitID { get; set; }
public String UnitName { get; set; }
// other definitions
}
控制器
using ProjectName.Models;
[RoutePrefix("Input")]
public class InputController : Controller
{
[HttpGet]
public ActionResult Winner()
{
WinnerModel model = new WinnerModel()
{
// default values on first visit/reload page
TranDate = DateTime.Now.Date,
UnitList = new List<UnitModel>(); // list declaration
}
return View(model);
}
public PartialViewResult CustomerData(String customerId, String sessionId, DateTime tranDate, WinnerModel model)
{
if (DevExpressHelper.IsCallback && !String.IsNullOrEmpty(customerId))
{
Session["CustomerID"] = customerId;
Session["SessionID"] = sessionId;
Session["TranDate"] = Convert.ToDateTime(tranDate);
using (var DB = new DBContext())
{
var query = DB.Customers.Where(c => c.CustomerID == customerId).FirstOrDefault();
// model property assignments
}
}
return PartialView("_CustomerData", model);
}
public PartialViewResult ShowItemsGrid(WinnerModel model)
{
String customerId = (Session["CustomerId"] ?? String.Empty).ToString();
String sessionId = (Session["SessionId"] ?? String.Empty).ToString();
String lastCustomer = (Session["LastCustomer"] ?? String.Empty).ToString();
DateTime tranDate = Convert.ToDateTime(Session["TranDate"] ?? DateTime.Now.Date);
using (var DB = new DBContext())
{
model.CustomerId = customerId;
model.SessionId = sessionId;
model.TranDate = tranDate;
model.UnitList = model.GetUnitList(sessionId, tranDate);
if (model.UnitList == null || model.UnitList.Count == 0)
{
model.UnitList = new List<UnitModel>();
}
Session["LastCustomer"] = lastCustomer;
return PartialView("_GridView", model);
}
}
}
查看 (Winner.cshtml)
@using ProjectName.Models
@model WinnerModel
@Html.EnableUnobtrusiveJavascript()
<script type="text/javascript">
var customer = null;
function initializeGrid()
{
ItemsGrid.PerformCallback(); // routine check if customer name exists
}
function comboChanged(s, e) {
customer = s.GetValue();
CustomerDataPanel.PerformCallback(); // callback to fill customer data for partial view & load units into gridview
}
// callback to insert values into session variable
function customerBeginCallback(s, e) {
e.customArgs["customerId"] = customer;
e.customArgs["sessionId"] = SessionId.GetValue();
e.customArgs["tranDate"] = TranDate.GetValue();
}
function customerEndCallback(s, e) {
ItemsGrid.PerformCallback();
}
// count checked data inside gridview
// this may be asked on other context and doesn't matter for this one
function countUnits(buttonName, url)
{
// other code
}
</script>
@using (Html.BeginForm("Winner", "Input", FormMethod.Post))
{
Html.DevExpress().TextBoxFor(m => m.SessionId, TextBoxSettings).GetHtml();
Html.DevExpress().DateEditFor(m => m.TranDate, DateEditSettings).GetHtml();
// this combobox has client-side event SelectedIndexChanged = "comboChanged"
// GetCustomers method just populate customers data into combobox and unrelated to this problem
Html.DevExpress().ComboBoxFor(m => m.CustomerId, ComboBoxSettings).BindList(ProjectName.Providers.GetCustomers()).GetHtml();
Html.RenderPartial("_CustomerData", Model); // DX callback panel
Html.RenderPartial("_GridView", Model);
// button to count all checked values inside gridview
Html.DevExpress().Button(CountButtonSettings).GetHtml();
Html.DevExpress().LabelFor(m => m.TotalPrice, PriceLabelSettings).GetHtml();
// button for submit & reset form here
Html.DevExpress().Button(SubmitButtonSettings).GetHtml();
Html.DevExpress().Button(ResetButtonSettings).GetHtml();
}
部分视图 (_CustomerData.cshtml)
@using ProjectName.Models
@model WinnerModel
@{
// MVC DX callback panel for customer details
// Name = CustomerDataPanel
// CallbackRouteValues: Controller = Input, Action = CustomerData
// ClientSideEvents.BeginCallback = customerBeginCallback
// ClientSideEvents.EndCallback = customerEndCallback
Html.DevExpress().CallbackPanel(CallbackPanelSettings).GetHtml();
}
部分视图 (_GridView.cshtml)
@using ProjectName.Models
@model WinnerModel
@{
// MVC DX GridView with row selection checkboxes
// The gridview column structure is exactly same as UnitModel has
// Name = ItemsGrid
// CallbackRouteValues: Controller = Input, Action = ShowItemsGrid
// ClientSideEvents.Init = initializeGrid
GridViewExtension grid = Html.DevExpress().GridView(GridViewSettings);
grid.Bind(Model.UnitList).GetHtml(); // grid bound to List<UnitModel>
}
所有 gridview 更改都需要足够的权限（即管理员/主管）。
问题陈述
我希望任何人帮助找出必须在控制器方法上附加用于清空 gridview 数据的适当例程代码的位置和方式，以提供预期的结果。正如我到目前为止所尝试的那样，当Winner重新访问或重新加载页面时，gridview 仍然保持其先前从会话变量给出的状态（登录后立即第一次访问有效，因为所有会话变量都是空的，因此没有数据填充到 gridview）。
此外，我想在用户尝试关闭/重新加载Winner页面时显示 JS 确认消息，同时检查一些/所有 gridview 数据。
预期成绩
- 对于每次第一次访问、重新访问和重新加载
Winner页面，gridview 内容必须为空。 - 用户提供特定客户 ID 后，gridview 将填充单元表中的一些单元数据，当用户接受重新加载/关闭页面确认消息时，其中的更改立即丢失。
任何类型的答案或建议将不胜感激。