you can use one of client side state management technique. i.e querystring
Using querystrings, you can pass the data(in your case it's country that inserted in database) from one page to very next page though url.
here 12 is the Id, for country in database.
you can read the values from url using following code
string countryName = Request.QueryString["countryName"];
int countryid = Convert.ToInt32(Request.QueryString["countryId"]);
If you mean locking the Dropdownlist is Disabling or read only.
ddlCountry.SelectedValue = countryName;
ddlCountry.Enabled = false;
Hope it will helps you..
Happy coding :)