using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Telerik.Web.UI;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void rgControl_PreRender(object sender, EventArgs e)
    {
        // I need 7 text boxes for column. So I am setting  EditFormColumnIndex 
        try
        {
            int j = 0, k = 1;
            foreach (GridColumn gc in RadGrid1.MasterTableView.AutoGeneratedColumns)
            {
                if (j < k * 7)
                {
                    gc.EditFormColumnIndex = k-1;
                }
                else
                {
                    k++;
                    gc.EditFormColumnIndex = k - 1;
                }
                j++;
            } ///  I think here is the mistake(for edited items) 
        }
        catch (Exception ex)
        {
        }
    }
}
