Grid View for ASP.NET Web Forms - How to implement an edit item template in batch mode

C#
using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Linq;
using DevExpress.Web.Data;
using DevExpress.Web;

public partial class _Default : System.Web.UI.Page {
    protected List<GridDataItem> GridData {
        get {
            var key = "34FAA431-CF79-4869-9488-93F6AAE81263";
            if(!IsPostBack || Session[key] == null)
                Session[key] = Enumerable.Range(0, 100).Select(i => new GridDataItem {
                    ID = i,
                    C1 = i % 2,
                    C2 = i * 0.5 % 3,
                    C3 = "C3 " + i,
                    C4 = i % 2 == 0,
                    C5 = new DateTime(2013 + i, 12, 16)
                }).ToList();
            return (List<GridDataItem>)Session[key];
        }
    }
    protected void Page_Load(object sender, EventArgs e) {
        Grid.DataSource = GridData;
        Grid.DataBind();

    }
    protected void Grid_RowInserting(object sender, ASPxDataInsertingEventArgs e) {
        InsertNewItem(e.NewValues);
        CancelEditing(e);
    }
    protected void Grid_RowUpdating(object sender, ASPxDataUpdatingEventArgs e) {
        UpdateItem(e.Keys, e.NewValues);
        CancelEditing(e);
    }
    protected void Grid_RowDeleting(object sender, ASPxDataDeletingEventArgs e) {
        DeleteItem(e.Keys, e.Values);
        CancelEditing(e);
    }
    protected void Grid_BatchUpdate(object sender, ASPxDataBatchUpdateEventArgs e) {
        foreach(var args in e.InsertValues)
            InsertNewItem(args.NewValues);
        foreach(var args in e.UpdateValues)
            UpdateItem(args.Keys, args.NewValues);
        foreach(var args in e.DeleteValues)
            DeleteItem(args.Keys, args.Values);

        e.Handled = true;
    }
    protected GridDataItem InsertNewItem(OrderedDictionary newValues) {
        var item = new GridDataItem() { ID = GridData.Count };
        LoadNewValues(item, newValues);
        GridData.Add(item);
        return item;
    }
    protected GridDataItem UpdateItem(OrderedDictionary keys, OrderedDictionary newValues) {
        var id = Convert.ToInt32(keys["ID"]);
        var item = GridData.First(i => i.ID == id);
        LoadNewValues(item, newValues);
        return item;
    }
    protected GridDataItem DeleteItem(OrderedDictionary keys, OrderedDictionary values) {
        var id = Convert.ToInt32(keys["ID"]);
        var item = GridData.First(i => i.ID == id);
        GridData.Remove(item);
        return item;
    }
    protected void LoadNewValues(GridDataItem item, OrderedDictionary values) {
        item.C1 = Convert.ToInt32(values["C1"]);
        item.C2 = Convert.ToDouble(values["C2"]);
        item.C3 = Convert.ToString(values["C3"]);
        item.C4 = Convert.ToBoolean(values["C4"]);
        item.C5 = Convert.ToDateTime(values["C5"]);
    }
    protected void CancelEditing(CancelEventArgs e) {
        e.Cancel = true;
        Grid.CancelEdit();
    }
    public class GridDataItem {
        public int ID { get; set; }
        public int C1 { get; set; }
        public double C2 { get; set; }
        public string C3 { get; set; }
        public bool C4 { get; set; }
        public DateTime C5 { get; set; }
    }


}

Visual Basic
Imports System
Imports System.Collections.Generic
Imports System.Collections.Specialized
Imports System.ComponentModel
Imports System.Linq
Imports DevExpress.Web.Data
Imports DevExpress.Web

Partial Public Class _Default
    Inherits System.Web.UI.Page

    Protected ReadOnly Property GridData() As List(Of GridDataItem)
        Get
            Dim key = "34FAA431-CF79-4869-9488-93F6AAE81263"
            If Not IsPostBack OrElse Session(key) Is Nothing Then
                Session(key) = Enumerable.Range(0, 100).Select(Function(i) New GridDataItem With {
                    .ID = i,
                    .C1 = i Mod 2,
                    .C2 = i * 0.5 Mod 3,
                    .C3 = "C3 " & i,
                    .C4 = i Mod 2 = 0,
                    .C5 = New DateTime(2013 + i, 12, 16)
                }).ToList()
            End If
            Return CType(Session(key), List(Of GridDataItem))
        End Get
    End Property
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        Grid.DataSource = GridData
        Grid.DataBind()

    End Sub
    Protected Sub Grid_RowInserting(ByVal sender As Object, ByVal e As ASPxDataInsertingEventArgs)
        InsertNewItem(e.NewValues)
        CancelEditing(e)
    End Sub
    Protected Sub Grid_RowUpdating(ByVal sender As Object, ByVal e As ASPxDataUpdatingEventArgs)
        UpdateItem(e.Keys, e.NewValues)
        CancelEditing(e)
    End Sub
    Protected Sub Grid_RowDeleting(ByVal sender As Object, ByVal e As ASPxDataDeletingEventArgs)
        DeleteItem(e.Keys, e.Values)
        CancelEditing(e)
    End Sub
    Protected Sub Grid_BatchUpdate(ByVal sender As Object, ByVal e As ASPxDataBatchUpdateEventArgs)
        For Each args In e.InsertValues
            InsertNewItem(args.NewValues)
        Next args
        For Each args In e.UpdateValues
            UpdateItem(args.Keys, args.NewValues)
        Next args
        For Each args In e.DeleteValues
            DeleteItem(args.Keys, args.Values)
        Next args

        e.Handled = True
    End Sub
    Protected Function InsertNewItem(ByVal newValues As OrderedDictionary) As GridDataItem
        Dim item = New GridDataItem() With {.ID = GridData.Count}
        LoadNewValues(item, newValues)
        GridData.Add(item)
        Return item
    End Function
    Protected Function UpdateItem(ByVal keys As OrderedDictionary, ByVal newValues As OrderedDictionary) As GridDataItem
        Dim id = Convert.ToInt32(keys("ID"))
        Dim item = GridData.First(Function(i) i.ID = id)
        LoadNewValues(item, newValues)
        Return item
    End Function
    Protected Function DeleteItem(ByVal keys As OrderedDictionary, ByVal values As OrderedDictionary) As GridDataItem
        Dim id = Convert.ToInt32(keys("ID"))
        Dim item = GridData.First(Function(i) i.ID = id)
        GridData.Remove(item)
        Return item
    End Function
    Protected Sub LoadNewValues(ByVal item As GridDataItem, ByVal values As OrderedDictionary)
        item.C1 = Convert.ToInt32(values("C1"))
        item.C2 = Convert.ToDouble(values("C2"))
        item.C3 = Convert.ToString(values("C3"))
        item.C4 = Convert.ToBoolean(values("C4"))
        item.C5 = Convert.ToDateTime(values("C5"))
    End Sub
    Protected Sub CancelEditing(ByVal e As CancelEventArgs)
        e.Cancel = True
        Grid.CancelEdit()
    End Sub
    Public Class GridDataItem
        Public Property ID() As Integer
        Public Property C1() As Integer
        Public Property C2() As Double
        Public Property C3() As String
        Public Property C4() As Boolean
        Public Property C5() As DateTime
    End Class


End Class