datacombo in datagrid

I have a webpage which retrieves data from a table and display it in a datagrid. This datagrid has edit, cancel, update and add new links. When i click on the edit or add new link, there appears a textbox in the fields. If i enter a value and update it works fine... but I dont want textbox there , instead I want a dropdown menu which should fetch data from another table. so that the user dont have to type but just select it...BUt these dropdown should only appear when I click on edit or new . Can it be done????

How can I do that...
My code is like this...


<%@ Page Language="VB" Debug="true" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.SqlClient" %>
<script runat="server">

    ' TODO: update the ConnectionString and Command values for your application
   
    Dim ConnectionString As String = "server=ser;uid=sa;pwd=sa;database=data;"

    Dim SelectCommand As String = "select FullName, GroupName from tblusers inner join tblwebaccess on tblwebaccess.id_user=tblusers.id_user inner join tblReports_AutoGen_GroupTypes on tblwebaccess.ID_reportgroup =tblReports_AutoGen_GroupTypes.ID_reportgroup order by fullname"
    Dim isEditing As Boolean = False
   
    Sub Page_Load(Sender As Object, E As EventArgs)
   
        If Not Page.IsPostBack Then
   
            ' Databind the data grid on the first request only
            ' (on postback, bind only in editing, paging and sorting commands)
   
            BindGrid()
   
        End If
   
    End Sub
   
    ' ---------------------------------------------------------------
    '
    ' DataGrid Commands: Page, Sort, Edit, Update, Cancel, Delete
    '
   
    Sub DataGrid_ItemCommand(Sender As Object, E As DataGridCommandEventArgs)
   
        ' this event fires prior to all of the other commands
        ' use it to provide a more graceful transition out of edit mode
   
        CheckIsEditing(e.CommandName)
   
    End Sub
   
    Sub CheckIsEditing(commandName As String)
   
        If DataGrid1.EditItemIndex <> -1 Then
   
            ' we are currently editing a row
            If commandName <> "Cancel" And commandName <> "Update" Then
   
                ' user's edit changes (If any) will not be committed
                Message.Text = "Your changes have not been saved yet.  Please press update to save your changes, or cancel to discard your changes, before selecting another item."
                isEditing = True
   
            End If
   
        End If
   
    End Sub
   
    Sub DataGrid_Edit(Sender As Object, E As DataGridCommandEventArgs)
   
        ' turn on editing for the selected row
   
        If Not isEditing Then
   
            DataGrid1.EditItemIndex = e.Item.ItemIndex
            BindGrid()
   
        End If
   
    End Sub
   
    Sub DataGrid_Update(Sender As Object, E As DataGridCommandEventArgs)
   
        ' update the database with the new values
   
        ' get the edit text boxes
        'Dim id As String = CType(e.Item.Cells(2).Controls(0), TextBox).Text
        Dim fullname As String = CType(e.Item.Cells(0).Controls(0), TextBox).Text
        Dim groupname As String = CType(e.Item.Cells(1).Controls(0), TextBox).Text
   
        ' TODO: update the Command value for your application
   
   
        Dim myConnection As New SqlConnection(ConnectionString)
        Dim UpdateCommand As SqlCommand = new SqlCommand()
        UpdateCommand.Connection = myConnection
   
        If AddingNew = True Then
            UpdateCommand.CommandText = "insert into tblwebaccess (id_user,id_reportgroup) select id_user,ID_reportgroup from tblusers,tblReports_AutoGen_GroupTypes where tblusers.fullname like '" & fullname &"%' and tblReports_AutoGen_GroupTypes.groupname like '" & groupname & "%'"
        Else
            'UpdateCommand.CommandText = "UPDATE authors SET au_lname = @au_lname, au_fname = @au_fname WHERE au_id = @au_id"
        End If
   
        'UpdateCommand.Parameters.Add("@au_id", SqlDbType.VarChar, 11).Value = id
        'UpdateCommand.Parameters.Add("@au_lname", SqlDbType.VarChar, 40).Value = lname
       ' UpdateCommand.Parameters.Add("@au_fname", SqlDbType.VarChar, 20).Value = fname
   
        ' execute the command
        Try
            myConnection.Open()
            UpdateCommand.ExecuteNonQuery()
   
        Catch ex1 as SQLException
             Message.Text="Record already present"
   
        Catch ex as Exception
            Message.Text = ex.ToString()
   
   
   
        Finally
            myConnection.Close()
   
        End Try
   
        ' Resort the grid for new records
        If AddingNew = True Then
            DataGrid1.CurrentPageIndex = 0
            AddingNew = false
        End If
   
        ' rebind the grid
        DataGrid1.EditItemIndex = -1
        BindGrid()
   
    End Sub
   
    Sub DataGrid_Cancel(Sender As Object, E As DataGridCommandEventArgs)
   
        ' cancel editing
   
        DataGrid1.EditItemIndex = -1
        BindGrid()
   
        AddingNew = False
   
    End Sub
   
    Sub DataGrid_Delete(Sender As Object, E As DataGridCommandEventArgs)
   
        ' delete the selected row
   
        If Not isEditing Then
   
            ' the key value for this row is in the DataKeys collection
            'Dim keyValue As String = CStr(DataGrid1.DataKeys(e.Item.ItemIndex))
            'response.write(e.Item.ItemIndex)
               'response.write(e.item.cells(3).text)
   
            ' TODO: update the Command value for your application
            Dim myConnection As New SqlConnection(ConnectionString)
            'Dim DeleteCommand As New SqlCommand("DELETE from tblwebaccess where id=" & keyValue , myConnection)
            Dim DeleteCommand As New SqlCommand("delete from tblwebaccess where id_user=(select id_user from tblusers where fullname like '" & e.item.cells(0).text &"') and id_ReportGroup=(select id_reportgroup from tblReports_AutoGen_GroupTypes where groupname like '" & e.item.cells(1).text & "')" , myConnection)
                        ' execute the command
            myConnection.Open()
            DeleteCommand.ExecuteNonQuery()
            myConnection.Close()
   
            ' rebind the grid
            DataGrid1.CurrentPageIndex = 0
            DataGrid1.EditItemIndex = -1
            BindGrid()
   
        End If
   
    End Sub
   
    Sub DataGrid_Page(Sender As Object, E As DataGridPageChangedEventArgs)
   
        ' display a new page of data
   
        If Not isEditing Then
   
            DataGrid1.EditItemIndex = -1
            DataGrid1.CurrentPageIndex = e.NewPageIndex
            BindGrid()
   
        End If
   
    End Sub
   
    Sub AddNew_Click(Sender As Object, E As EventArgs)
   
        ' add a new row to the end of the data, and set editing mode 'on'
   
        CheckIsEditing("")
   
        If Not isEditing = True Then
   
            ' set the flag so we know to do an insert at Update time
            AddingNew = True
   
            ' add new row to the end of the dataset after binding
   
            ' first get the data
            Dim myConnection As New SqlConnection(ConnectionString)
            Dim myCommand As New SqlDataAdapter(SelectCommand, myConnection)
   
            Dim ds As New DataSet()
            myCommand.Fill(ds)
   
            ' add a new blank row to the end of the data
            Dim rowValues As Object() = {"", ""}
            ds.Tables(0).Rows.Add(rowValues)
   
            ' figure out the EditItemIndex, last record on last page
            Dim recordCount As Integer = ds.Tables(0).Rows.Count
   
            If recordCount > 1 Then
   
                recordCount -= 1
                DataGrid1.CurrentPageIndex = recordCount \ DataGrid1.PageSize
                DataGrid1.EditItemIndex = recordCount Mod DataGrid1.PageSize
   
            End If
   
            ' databind
            DataGrid1.DataSource = ds
            DataGrid1.DataBind()
   
        End If
   
   
    End Sub
   
    ' ---------------------------------------------------------------
    '
    ' Helpers Methods:
    '
   
    ' property to keep track of whether we are adding a new record,
    ' and save it in viewstate between postbacks
   
    Property AddingNew() As Boolean
   
        Get
            Dim o As Object = ViewState("AddingNew")
            If o Is Nothing Then
                Return False
            End If
            Return CBool(o)
        End Get
   
        Set(ByVal Value As Boolean)
            ViewState("AddingNew") = Value
        End Set
   
    End Property
   
    Sub BindGrid()
   
        Dim myConnection As New SqlConnection(ConnectionString)
        Dim myCommand As New SqlDataAdapter(SelectCommand, myConnection)
   
        Dim ds As New DataSet()
        myCommand.Fill(ds)
   
        DataGrid1.DataSource = ds
        DataGrid1.DataBind()
        'DataGrid1.columns(0).visible=false
    End Sub

</script>
<html>
<head>
</head>
<body style="FONT-FAMILY: arial">
    <h2>Web Access Control
    </h2>
    <hr size="1" />
    <form runat="server">
        <asp:datagrid id="DataGrid1" runat="server" width="80%" CellSpacing="1" GridLines="None" CellPadding="3" BackColor="White" ForeColor="Black" OnPageIndexChanged="DataGrid_Page" PageSize="6" AllowPaging="true" OnDeleteCommand="DataGrid_Delete" OnCancelCommand="DataGrid_Cancel" OnUpdateCommand="DataGrid_Update" OnEditCommand="DataGrid_Edit" OnItemCommand="DataGrid_ItemCommand" DataKeyField="" AutoGenerateColumns="False" AllowSorting="True">
            <FooterStyle backcolor="#C6C3C6"></FooterStyle>
            <PagerStyle mode="NumericPages" backcolor="#C6C3C6" font-size="Smaller" horizontalalign="Right"></PagerStyle>
            <AlternatingItemStyle backcolor="PaleGoldenrod"></AlternatingItemStyle>
            <ItemStyle backcolor="Beige"></ItemStyle>
            <HeaderStyle backcolor="#4A3C8C" forecolor="White" font-bold="True"></HeaderStyle>
            <Columns>
                <asp:BoundColumn DataField="FullName" HeaderText="Full Name"></asp:BoundColumn>
                <asp:BoundColumn DataField="GroupName" HeaderText="Group Name"></asp:BoundColumn>

                <asp:EditCommandColumn CancelText="Cancel" UpdateText="Update" EditText="Edit">
                    <ItemStyle width="10%" font-size="Smaller"></ItemStyle>
                </asp:EditCommandColumn>
                <asp:ButtonColumn CommandName="Delete" Text="Delete">
                    <ItemStyle width="10%" font-size="Smaller"></ItemStyle>
                </asp:ButtonColumn>
            </Columns>
        </asp:datagrid>
        <br />
        <asp:LinkButton id="LinkButton1" onclick="AddNew_Click" runat="server" Font-Size="smaller" Text="Add new item"></asp:LinkButton>
        <br />
        <br />
        <asp:Label id="Message" runat="server" width="80%" enableviewstate="false" forecolor="red"></asp:Label>
    </form>
</body>
</html>