How to Reload value in combobox?

Dear Friends,

                 I would Like to one thing about The Reloading one value in  Combobox   Control.

  Here i Show the What i really Expect ..

          CountryName

                          The above value to be reloaded from the Db, to the comboCountry Id ...

1.                         cmobox.selecteditem.Text=_dt.Rows[0]["COUNTRY"].ToString();

2.                        ddlCountry.SelectedIndex =ddlCountry.Items.IndexOf(ddlCountry.Items.FindByText(_dt.Rows[0]["Country"].ToString().Trim()));

 

                 The above coding not working , In If not ispostback section , i have loaded on the County Comboboxxx..

Those above two not woking ..too

Thanks in Advance