Show Hide TextBox and DropDownList inside ASP.Net GridView using Container.DataItemIndex property

Hi all,

in my example i have one gridview with following data.

                                                <asp:GridView ID="GvData" runat="server" AutoGenerateColumns="false" ShowHeader="false"  Width="1200px">
                                                    <Columns>
                                                        <asp:TemplateField HeaderText="Column1">
                                                            <ItemTemplate>
                                                                <asp:Label ID="Section_Column1" runat="server" Text='<%# Eval("Section_Column1") %>' Width="50px" />
                                                            </ItemTemplate>
                                                        </asp:TemplateField>                                                      
                                                        <asp:TemplateField>
                                                            <ItemTemplate>
                                                                <asp:TextBox runat="server" ID="Txt1Data" Text='<%# Eval("Txt1_Data") %>' Width="500px" />

                                                                <asp:DropDownList ID="ddl1_Data" runat="server" >
                                                                <asp:ListItem Value="Y">Yes</asp:ListItem>
                                                                <asp:ListItem Value="N">No</asp:ListItem>
                                                                </asp:DropDownList>
                                                             </ItemTemplate>
                                                        </asp:TemplateField>
                                                    </Columns>
                                                </asp:GridView>

i am databind the above gridview

        private void BindGvData()
        {
            DataTable dt = new DataTable();

            //Add columns to DataTable.
            dt.Columns.AddRange(new DataColumn[2] { new DataColumn("Section_Column1"), new DataColumn("Txt1_Data") });


            //Add rows to DataTable.
          
            dt.Rows.Add("1", "1st row");
            dt.Rows.Add("2", "");
            dt.Rows.Add(3, "");            

            GvData.DataSource = dt;
            GvData.DataBind();
        }

after binding the data i want to display gridview below like this at 1st row textbox visible with data if have and dropdownlist not visible.

at 2nd row dropdownlist visible and textbox not visible. 

at 3rd row textbox visible with data if have and dropdownlist not visible.

how to do acheive this.. 

Thanks in advance