DropdownList in MVC Strongly Typed

View

 <div class="editor-label">
            Country
        </div>
        <div class="editor-field">
         
            @Html.DropDownListFor(model=>model.CountryId, new SelectList((ViewBag.Countries) as SelectList, "Value", "Text"), "Select")
        </div>


-----------------------------------
Controller
  CountryDA countryda = new CountryDA ();
 ViewBag.Countries =new SelectList(countryda.ReadAllCountry(), "CountryId", "CountryName", _country.CountryId);
     
-------------------------------
DATA Access

  public List<Country> ReadAllCountry()
        {
            List<Country> country = new List<Country>();
            try
            {
                using (SqlConnection con = new SqlConnection(connectionstring))
                {
                    SqlCommand com = new SqlCommand("Usp_ReadAllCountry", con);
                    com.CommandType = CommandType.StoredProcedure;
                    con.Open();
                    SqlDataReader dr = com.ExecuteReader();

                    while (dr.Read())
                    {
                        country.Add(new Country { CountryId = Convert.ToInt32(dr["CountryId"]), CountryName = Convert.ToString(dr["CountryName"]) });
                    }
                }
            }
            catch
            {
                throw;
            }
            return country;
        }

---------------------------------------
Model
   public class Country
    {
        public int CountryId { get; set; }
        public string CountryName { get; set; }
    }