System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Reflection;

using System.Web.UI;

using Telerik.Web.UI;

namespace GridColumns

{

public partial class _Default : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

    }

}

CodeBehind Class

DataObject(true)]

public class BusinessLogic

{

    public List<BusinessObject> GetList()

    {

        List<BusinessObject> list = new List<BusinessObject>();

        list.Add(

new BusinessObject() { ID = 1, Name = "A" });

        list.Add(

new BusinessObject() { ID = 2, Name = "B" }); 
        list.Add(new BusinessObject() { ID = 3, Name = "C" });
        list.Add(new BusinessObject() { ID = 4, Name = "D" });

        return list;

    }

    public List<ChildObject> GetChildren(int parentID)

    {

        List<ChildObject> list = new List<ChildObject>();

        list.Add(

new ChildObject() { ID = 100, Parent = parentID, Data = "QWE" });

        list.Add(

new ChildObject() { ID = 101, Parent = parentID, Data = "RTY" });

        return list;

    }

}

public class BusinessObject

{

    public int ID { get; set; }

    public string Name { get; set; }

}

public class ChildObject

{

    public int ID { get; set; }

    public int Parent { get; set; }

    public string Data { get; set; }

}

Business Objects

TemplateColumn Classes

public class MyTemplateColumn : GridTemplateColumn

{

    public override void Initialize()

    {

        base.Initialize();

        this.ItemTemplate = new MyTemplate(this.DataField);

    }

}

public class MyTemplate : ITemplate

{

    private LiteralControl lControl;

    private string colname;

    public MyTemplate(string cName)

    {

        colname = cName;

    }

    public void InstantiateIn(System.Web.UI.Control container)

    {

        lControl =

new LiteralControl();

        lControl.ID =

"lControl";

        lControl.DataBinding +=

new EventHandler(lControl_DataBinding);

        container.Controls.Add(lControl);
    }

    public void lControl_DataBinding(object sender, EventArgs e)

    {

        LiteralControl l = (LiteralControl)sender;

        GridDataItem container = (GridDataItem)l.NamingContainer;

        PropertyInfo property = typeof(BusinessObject).GetProperty(colname);

        l.Text = property.GetValue(container.DataItem,

null).ToString();

    }

}

TemplateColumn Classes

}

ASPX File
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="GridColumns._Default" %>

<%

@ Register assembly="Telerik.Web.UI" namespace="Telerik.Web.UI" tagprefix="telerik" %>

<%

@ Register assembly="GridColumns" namespace="GridColumns" tagprefix="me" %>

DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<

html xmlns="http://www.w3.org/1999/xhtml" >

<

head runat="server">

<title></title>

</

head>

<

body>

<form id="form1" runat="server">

    <asp:ScriptManager ID="ScriptManager1" runat="server"> </asp:ScriptManager>

    <div>

    <telerik:RadGrid ID="RadGrid1" runat="server" DataSourceID="ObjectDataSource1" 
                    GridLines="None" AutoGenerateColumns="False">

 
        <

MasterTableView CellSpacing="-1" DataKeyNames="ID" DataSourceID="ObjectDataSource1">

            <DetailTables>

                <telerik:GridTableView runat="server" CellSpacing="-1" DataKeyNames="ID" DataSourceID="ObjectDataSource2">

                <ParentTableRelation>
                    <telerik:GridRelationFields DetailKeyField="ParentID" MasterKeyField="ID" />
                </ParentTableRelation>

               <Columns>

                    <telerik:GridBoundColumn DataField="ID" DataType="System.Int32" HeaderText="ID" UniqueName="ID">
                    </telerik:GridBoundColumn>

                    <telerik:GridBoundColumn DataField="Data" HeaderText="Data" UniqueName="Data"> 

                    </telerik:GridBoundColumn>

                </Columns>

                <RowIndicatorColumn><HeaderStyle Width="20px" /></RowIndicatorColumn>

                <ExpandCollapseColumn><HeaderStyle Width="20px" /></ExpandCollapseColumn>

            </telerik:GridTableView>

        </DetailTables>

        <

RowIndicatorColumn><HeaderStyle Width="20px"></HeaderStyle></RowIndicatorColumn>

        <

ExpandCollapseColumn Visible="True"><HeaderStyle Width="20px"></HeaderStyle></ExpandCollapseColumn>
        <Columns>

            <telerik:GridBoundColumn DataField="ID" DataType="System.Int32" HeaderText="ID" UniqueName="ID">

            </telerik:GridBoundColumn>

            <!-- Standard Template Column -->

            <telerik:GridTemplateColumn DataField="Name" HeaderText="Name" UniqueName="Name">

                <EditItemTemplate>

                    <asp:TextBox ID="NameTextBox" runat="server" Text='<%# Bind("Name") %>'></asp:TextBox>

                </EditItemTemplate>

                <ItemTemplate>

                    <asp:Label ID="NameLabel" runat="server" Text='<%# Eval("Name") %>'></asp:Label>

                </ItemTemplate>

</telerik:GridTemplateColumn>

<!-- Subclassed Template Column -->

            <me:MyTemplateColumn DataField="Name" HeaderText="Name" UniqueName="Name"> 

            </me:MyTemplateColumn>

        </Columns>

    </

MasterTableView>

</telerik:RadGrid>

<asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="GetList" 
            TypeName="GridColumns.BusinessLogic">
</asp:ObjectDataSource>

<asp:ObjectDataSource ID="ObjectDataSource2" runat="server" SelectMethod="GetChildren" 
            TypeName="GridColumns.BusinessLogic">

    <SelectParameters>

        <asp:Parameter Name="parentID" Type="Int32" />

    </SelectParameters>

</asp:ObjectDataSource>

</div>

</form>

</

body>

</

html>

Thanks