public class CasecadeDropdown : System.Web.Services.WebService
{
string Constr = ConfigurationManager.AppSettings["MyConnectionString"].ToString();
public CasecadeDropdown ()
{
}
in your webservice you must to remove comment line from
public class CasecadeDropdown : System.Web.Services.WebService
{
like this
[System.Web.Script.Services.ScriptService]
public class CasecadeDropdown : System.Web.Services.WebService
{
and pls add this to your state cascadedropdown
ParentControlID="ddlCountry"
and edit here
List<cascadingdropdownnamevalue> countrydetails = new List<cascadingdropdownnamevalue>();
to
List<CascadingDropDownNameValue> countrydetails = new List<CascadingDropDownNameValue>();
because of c# is a case sensitive language