I've a SharePoint List named Promotions and following are sample data in it.
PromotionID    Promotions        Active
1                          Promotion 1         Yes
2                          Promotion 2         Yes
3                          Promotion 3          No
4                          Promotion 4          No

I also one another SharePoint list called StorePromotions
StorePromoID    Promotions(Promotions List Look Up Column)    Region(Regions List Look Up Column) ...    
1                            Promotion 4                                                                    Region 3
2                            Promotion 3                                                                    Region 5

When I try to update the StorePromotion List, I choose Promotions from GridDropDownColumn(which I bind earlier with Promotions List) by getting the value from SelectedValue property(ie., storePromo.TradeName = tradeEditor.SelectedValue;). But when I update the list I get error, because I need the "PromotionID" and NOT the SelectedValue. Can anyone tell me how I can get that?

For more information, here is my code
StorePromotions.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="StorePromotionsByTrade.aspx.cs"
    Inherits="Heritage.Internet.UI.Pages.ContentManager.StorePromotionsByTrade,Heritage.Internet.UI.Pages.ContentManager,Culture=neutral, Version=1.0.0.0, PublicKeyToken=1202d49d749de830"
    MasterPageFile="~/_layouts/HP/application.master" EnableSessionState="True"%>

<%@ Register Assembly="Telerik.Web.UI, Version=2010.1.309.20, Culture=neutral, PublicKeyToken=121fae78165ba3d4"
    Namespace="Telerik.Web.UI" TagPrefix="telerik" %>
<%@ Register Assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
    Namespace="System.Web.UI" TagPrefix="asp" %>
<%@ Register Tagprefix="SharePoint" Namespace="Microsoft.SharePoint.WebControls" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Register Tagprefix="Utilities" Namespace="Microsoft.SharePoint.Utilities" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Import Namespace="Microsoft.SharePoint" %>
<%@ Register TagPrefix="wssuc" TagName="ButtonSection" src="~/_controltemplates/ButtonSection.ascx" %>
<%@ Register TagPrefix="wssuc" TagName="InputFormControl" src="~/_controltemplates/InputFormControl.ascx" %>
<%@ Register TagPrefix="wssuc" TagName="InputFormSection" src="~/_controltemplates/InputFormSection.ascx" %>
<%@ Register Tagprefix="wssawc" Namespace="Microsoft.SharePoint.WebControls" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Register Tagprefix="SharePoint" Namespace="Microsoft.SharePoint.WebControls" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<asp:Content ID="Content1" contentplaceholderid="PlaceHolderAdditionalPageHead" runat="server"></asp:Content>
<asp:Content ID="Content2" contentplaceholderid="PlaceHolderPageTitle" runat="server"></asp:Content>
<asp:Content ID="Content3" contentplaceholderid="PlaceHolderPageTitleInTitleArea" runat="server">Store Promotions assigned by TradeName</asp:Content>
<asp:Content ID="Content4" ContentPlaceHolderId="PlaceHolderPageDescription" runat="server">
    <asp:ScriptManager ID="ScriptManager1" runat="server" />
</asp:Content>
<asp:Content ID="Content5" ContentPlaceHolderId="PlaceHolderMain" runat="server">
    <telerik:RadGrid ID="radGridStorePromotions" runat="server" GridLines="None" AutoGenerateColumns="false"
        AllowPaging="true" AllowSorting="true" OnNeedDataSource="radGridStorePromotions_OnNeedDataSource"
        OnItemDataBound="radGridStorePromotions_OnItemDataBound" OnItemCreated="radGridStorePromotions_ItemCreated"
        OnUpdateCommand="radGridStorePromotions_OnUpdateCommand" >
        <PagerStyle Mode="NextPrevAndNumeric" />
        <MasterTableView TableLayout="Fixed" Height="100%"  AllowFilteringByColumn="True">
            <Columns>
                <telerik:GridNumericColumn HeaderText="ID" DataField="ID" ReadOnly="true" Visible="false" UniqueName="PromoIdUniqueName" />
                <telerik:GridDropDownColumn HeaderText="Promotion" UniqueName="PromotionsUniqueName"
                         DataField="Promotion" ListTextField="Promotion" ListValueField="Promotion" ListDataMember="Title"  /> 
                <telerik:GridDropDownColumn HeaderText="TradeName" UniqueName="TradeNameUniqueName"
                         DataField="TradeName" ListTextField="TradeName" ListValueField="TradeName" ListDataMember="Title" 
                         DropDownControlType="RadComboBox" />
                <telerik:GridDropDownColumn HeaderText="StoreLocation" UniqueName="StoreLocUniqueName"
                         DataField="StoreLocation" ListTextField="StoreLocation" ListValueField="StoreLocation"
                         ListDataMember="Title" />
                <telerik:GridDateTimeColumn HeaderText="Start Date" UniqueName="StartDateUniqueName" DataField="StartDate" />
                <telerik:GridDateTimeColumn HeaderText="End Date" UniqueName="EndDateUniqueName" DataField="EndDate" />
                <telerik:GridCheckBoxColumn HeaderText="Active" UniqueName="ActiveUniqueName" DataField="Active" />
                <telerik:GridEditCommandColumn HeaderText="Edit" UniqueName="EditCommandColumn" ButtonType="LinkButton"
                         EditText="Edit" UpdateText="Update" CancelText="Cancel" />
                <telerik:GridButtonColumn HeaderText="Delete" UniqueName="DeleteColumn" Text="Delete" CommandName="Delete" />
            </Columns>
        </MasterTableView>
    </telerik:RadGrid>
</asp:Content>

And this is my StorePromotions.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Heritage.Internet.BLL.Promotions;
using Heritage.Internet.BOL.Promotions;
using Heritage.Internet.BLL.Regions;
using Heritage.Internet.BOL.Regions;
using Heritage.Internet.BLL.StoreLocations;
using Heritage.Internet.BOL.StoreLocations;
using Heritage.Internet.BLL.StorePromotions;
using Heritage.Internet.BOL.StorePromotions;
using Heritage.Internet.BLL.TradeNames;
using Heritage.Internet.BOL.TradeNames;
using Telerik.Web.UI;

namespace Heritage.Internet.UI.Pages.ContentManager
{
    public partial class StorePromotionsByTrade : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                StorePromotionsBindData();
            }
        }

        protected void radGridStorePromotions_OnNeedDataSource(object source, GridNeedDataSourceEventArgs e)
        {
            if (Session["AllStorePromotions"] != null)
            {
                radGridStorePromotions.DataSource = Session["AllStorePromotions"];
            }
            else
            {
                StorePromotionsBindData();
            }
        }

        protected void radGridStorePromotions_OnItemDataBound(object sender, GridItemEventArgs e)
        {
            if (e.Item is GridEditableItem && e.Item.IsInEditMode)
            {
                GridEditableItem gridEditFormItem = (GridEditableItem)e.Item;
                GridEditManager gridEditMan = gridEditFormItem.EditManager;

                RadComboBox ddlTradeName = gridEditFormItem["TradeNameUniqueName"].Controls[0] as RadComboBox;

                GridDropDownColumnEditor promotionsEditor = gridEditMan.GetColumnEditor("PromotionsUniqueName") as GridDropDownColumnEditor;
                GridDropDownColumnEditor tradeEditor = gridEditMan.GetColumnEditor("TradeNameUniqueName") as GridDropDownColumnEditor;
                GridDropDownColumnEditor storeEditor = gridEditMan.GetColumnEditor("StoreLocUniqueName") as GridDropDownColumnEditor;
               
                //Get all ACTIVE Promotions in ASCENDING order and bind it to Promotions DropDownList
                /****************************************************************/
                //Storing the promotions in Session variable doesn't work.
                //It binds StorePromotions varibales to Promotions DropDownList.
                /****************************************************************/
                Promotion promotionBLL = new Promotion();
                List<PromotionEntity> promotions = new List<PromotionEntity>();
                promotions = promotionBLL.GetAllPromotions();
                object tempPromotions = promotionsEditor.DataSource;
                promotionsEditor.DataSource = promotions;
                promotionsEditor.DataBind();
                promotionsEditor.DataSource = tempPromotions;
               
                //Get ACTIVE Trade Names in ASCENDING order and bind it to TradeName DropDownList
                TradeName tradeNameBLL = new TradeName();
                List<TradeNameEntity> tradeNames = new List<TradeNameEntity>();
                tradeNames = tradeNameBLL.GetAllTradeNames();
                object tempTradeNames = tradeEditor.DataSource;
                tradeEditor.DataSource = tradeNames;
                tradeEditor.DataBind();
                tradeEditor.SelectedValue = ddlTradeName.SelectedValue;
                tradeEditor.DataSource = tempTradeNames;

                //Get ACTIVE Stores filtered by Selected TardeName and bind it to StoreLocations DropDownList
                StoreLocation storeLocBLL = new StoreLocation();
                List<StoreLocationListEntity> storeLocationsList = new List<StoreLocationListEntity>();
                storeLocationsList = storeLocBLL.GetStoresByTradeName(ddlTradeName.SelectedValue);
                object tempDataSource = storeEditor.DataSource;
                storeEditor.DataSource = storeLocationsList;
                storeEditor.DataBind();
                storeEditor.DataSource = tempDataSource;
            }
        }

        protected void radGridStorePromotions_ItemCreated(object sender, Telerik.Web.UI.GridItemEventArgs e)
        {
            if (e.Item is GridEditableItem && e.Item.IsInEditMode)
            {
                //the dropdown list will be the first control in the Controls collection of the corresponding cell
                RadComboBox ddlTradeName = (e.Item as GridEditableItem)["TradeNameUniqueName"].Controls[0] as RadComboBox;
               
                //attach SelectedIndexChanged event for the combobox control
                ddlTradeName.AutoPostBack = true;
                ddlTradeName.SelectedIndexChanged += new RadComboBoxSelectedIndexChangedEventHandler(ddlTradeName_OnSelectedIndexChanged);
            }
        }

        protected void ddlTradeName_OnSelectedIndexChanged(object sender, RadComboBoxSelectedIndexChangedEventArgs e)
        {
            GridEditableItem editedItem = (sender as RadComboBox).NamingContainer as GridEditableItem;
            RadComboBox ddlStoreLoc = editedItem["StoreLocUniqueName"].Controls[0] as RadComboBox;

            StoreLocation storeLocBLL = new StoreLocation();
            List<StoreLocationListEntity> storeLocationsList = new List<StoreLocationListEntity>();

            storeLocationsList = storeLocBLL.GetStoresByTradeName((editedItem["TradeNameUniqueName"].Controls[0] as RadComboBox).SelectedValue);
            ddlStoreLoc.ClearSelection();
            ddlStoreLoc.DataSource = storeLocationsList;
            ddlStoreLoc.DataBind();
        }

        protected void radGridStorePromotions_OnUpdateCommand(object source, GridCommandEventArgs e)
        {
            GridEditableItem gridEditFormItem = (GridEditableItem)e.Item;
            GridEditManager gridEditMan = gridEditFormItem.EditManager;

            GridNumericColumnEditor idEditor = gridEditMan.GetColumnEditor("PromoIdUniqueName") as GridNumericColumnEditor;
            GridDropDownColumnEditor promotionsEditor = gridEditMan.GetColumnEditor("PromotionsUniqueName") as GridDropDownColumnEditor;
            GridDropDownColumnEditor tradeEditor = gridEditMan.GetColumnEditor("TradeNameUniqueName") as GridDropDownColumnEditor;
            GridDropDownColumnEditor storeEditor = gridEditMan.GetColumnEditor("StoreLocUniqueName") as GridDropDownColumnEditor;
            GridDateTimeColumnEditor startDtEditor = gridEditMan.GetColumnEditor("StartDateUniqueName") as GridDateTimeColumnEditor;
            GridDateTimeColumnEditor endDtEditor = gridEditMan.GetColumnEditor("EndDateUniqueName") as GridDateTimeColumnEditor;
            GridCheckBoxColumnEditor activeEditor = gridEditMan.GetColumnEditor("ActiveUniqueName") as GridCheckBoxColumnEditor;

            StorePromotion storePromoBLL = new StorePromotion();
            StorePromotionListEntity storePromo = new StorePromotionListEntity();

            storePromo.ID = Convert.ToInt32(idEditor.Text);
            storePromo.Promotion = promotionsEditor.SelectedValue;
            int s = promotionsEditor.SelectedIndex;
            string d = promotionsEditor.SelectedText;
            storePromo.TradeName = tradeEditor.SelectedValue;
            storePromo.StoreLocation = storeEditor.SelectedValue;
            storePromo.StartDate = Convert.ToDateTime(startDtEditor.Text);
            storePromo.EndDate = Convert.ToDateTime(endDtEditor.Text);
            storePromo.Active = activeEditor.Value;

            storePromoBLL.UpdateStorePromotionToList(storePromo);

            StorePromotionsBindData();
        }

        private void StorePromotionsBindData()
        {
            //Get ALL Store Promotions in ASCENDING Order
            StorePromotion storePromosBLL = new StorePromotion();
            List<StorePromotionListEntity> storePromos = new List<StorePromotionListEntity>();
            storePromos = storePromosBLL.GetStorePromotionsAssignedByTrade();

            radGridStorePromotions.DataSource = storePromos;
            Session["AllStorePromotions"] = storePromos;
            radGridStorePromotions.DataBind();
        }
    }
}

I've finish this task by EOD tomorrow. If anyone could help me find this, it'd be really helpful.

Thank you.
K

this._middleRightBar.setAttribute("unselectable","on");

if (e.Value.ToUpper() == "DEFAULT")

{

gv.MasterTableView.GetColumn(

"colMainName").Visible = true;

}

if (e.Value.ToUpper() == "WEBVALIDATION")

{

gv.MasterTableView.GetColumn(

"colMainName").Visible = false;

}

Thanks.

Mark