DetailsView Control Edit with code behind

Hello everyone

ASP.NET 2.0
C#.NET

I have a DetailsView Control and it is bind to the db from the code behind. And now i want to edit the detailsview and submit the changes from code behind only. When i click Edit link on the bottom, the detailsView doesn't get changed into Textfields for each boundField ? I am new to this control. And i dont know to capture the edit click event from the code behind? I dont understand where i am getting wrong. Please give ur help. Please fill up the gaps in the below code.

Code:- ASPX page
########################################
<asp:DetailsView ID="DV_Company" runat="server"
                                     AutoGenerateRows="False" DataKeyNames="Hotelier_id"
                                    CellPadding="4" ForeColor="#333333" GridLines="None"
                                     AutoGenerateEditButton="true"
                                      OnModeChanging="DV_Company_ModeChanging"                          
                                    Width="90%" CellSpacing="5">
                                        <Fields>                                        
                                        <asp:BoundField HeaderText="Company" DataField="company_name" />
                                        <asp:BoundField HeaderText="Address" DataField="Address_details" />
                                        <asp:BoundField HeaderText="Contact Person" DataField="Contact_Person" />
                                        <asp:BoundField HeaderText="Phone1" DataField="Phone2" />
                                        <asp:BoundField HeaderText="Mobile" DataField="mobile_number" />
                                        <asp:BoundField HeaderText="FAX" DataField="fax_number" />
                                        <asp:BoundField HeaderText="Email" DataField="email_id" />
                                       
                                        </Fields>                                  
                                     
                                    </asp:DetailsView>
                                   
########################################

ASPX.CS code behind code.


 protected void Page_Load(object sender, EventArgs e)
    {
        if (Session["Session_UserName"] != null)
        {
            if (!Page.IsPostBack)
            {
                BindDV();
            }
        }
    }
    private void BindDV()
    {
        DataSet DSView = new DataSet();
        DSView = Globalfn.DataSource_Extract("SP_Select_HotelDetails_From_HotelID", Session["HotelierID"], "EHotelId");

        DV_Company.DataSource = DSView;
        DV_Company.DataBind();
    }

    protected void DV_Company_ModeChanging(object sender, DetailsViewModeEventArgs e)
    {
        DV_Company.DefaultMode = DetailsViewMode.Edit;
    }