Как привязать dropdownlist в модели сущностей ADO

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//DataAccessLayer

public List<Country> GetCountry()
       {
           try
           {
               return HRMModel.Countries.ToList();
           }
           catch (Exception)
           {

               throw;
           }
       }
       public List<State> GetStates(int countryId)
       {
           return (from s in HRMModel.States
                   where s.CountryId == countryId
                   select s).ToList();

       }
 public List<EmployeeModel> GetCountry()
        {
            var countryModelList = new List<EmployeeModel>();
            var countryList = dataAccess.GetCountry();
            if (countryList != null && countryList.Count > 0)
            {
                foreach (var country in countryList)
                {
                    var countryModel = new EmployeeModel();
                    countryModel.CountryId = country.CountryId;
                    countryModel.CountryName = country.CountryName;
                    countryModelList.Add(countryModel);
                }

            }
            return countryModelList;
        }
//Form ModelLayer
        public List<EmployeeModel> GetStateOnId(int countryId)
        {
            var stateModelList = new List<EmployeeModel>();
            var stateList = dataAccess.GetStates(countryId);

            foreach (var state in stateList)
            {

                var Model = new EmployeeModel();
                Model.StateId = state.StateId;
                Model.StateName = state.StateName;
                stateModelList.Add(Model);
            }
            return stateModelList;
        }
//From Cshtml code
<pre lang="HTML"><pre lang="HTML">

Страна @Html. DropDownListFor(m => m.CountryId, new SelectList(Model.Страны, "CountryId"," CountryName"), "SelectOne", new {@onchange= " GetStates ()", style= " width:170px" })
Государство @Html. DropDownListFor( m=> m.StateId,new SelectList(Model.Состояния, "StateId", " StateName"))
Что я уже пробовал:

я попытался связать dropdownList с помощью метода json, модели, dataAccessLayer и ado.net работа с фреймом сущности

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