public ActionResult Edit(int id, OpiniaModel opiniaModel)
        {
            if (ModelState.IsValid)
            {
                DataTable dtOpinia = new DataTable();
                string    nameUser = User.Identity.Name;

                using (SqlConnection sqlCon = new SqlConnection(connectionString))
                {
                    sqlCon.Open();

                    string     query  = "SELECT id FROM KONTO WHERE login_user=@UserName";
                    SqlCommand sqlCmd = new SqlCommand(query, sqlCon);
                    sqlCmd.Parameters.AddWithValue("@UserName", nameUser);
                    int idCurrentUser = Convert.ToInt32(sqlCmd.ExecuteScalar());

                    query = "select opis from opinia p INNER JOIN klient k " +
                            "ON p.klient_id = k.id INNER JOIN KONTO ko " +
                            "ON ko.id = k.konto_id WHERE ko.id = @KlientID and p.pracownik_id=@PracownikID;";
                    SqlDataAdapter sqlDa = new SqlDataAdapter(query, sqlCon);
                    sqlDa.SelectCommand.Parameters.AddWithValue("@PracownikID", id);
                    sqlDa.SelectCommand.Parameters.AddWithValue("@KlientID", idCurrentUser);

                    sqlDa.Fill(dtOpinia);

                    query  = "SELECT id FROM klient WHERE konto_id=@UserName";
                    sqlCmd = new SqlCommand(query, sqlCon);
                    sqlCmd.Parameters.AddWithValue("@UserName", idCurrentUser);
                    int id_klient = Convert.ToInt32(sqlCmd.ExecuteScalar());

                    if (dtOpinia.Rows.Count == 1)
                    {
                        query = "UPDATE opinia SET opis=@Opis " +
                                "WHERE pracownik_id=@PracownikID AND klient_id=@KlientID";
                        sqlCmd = new SqlCommand(query, sqlCon);
                        sqlCmd.Parameters.AddWithValue("@PracownikID", id);
                        sqlCmd.Parameters.AddWithValue("@KlientID", id_klient);
                        sqlCmd.Parameters.AddWithValue("@Opis", opiniaModel.Opis);
                        sqlCmd.ExecuteNonQuery();
                    }
                    else if (dtOpinia.Rows.Count == 0)
                    {
                        query  = "INSERT INTO opinia VALUES(@KlientID, @PracownikID, @Opis)";
                        sqlCmd = new SqlCommand(query, sqlCon);
                        sqlCmd.Parameters.AddWithValue("@KlientID", id_klient);
                        sqlCmd.Parameters.AddWithValue("@PracownikID", id);
                        sqlCmd.Parameters.AddWithValue("@Opis", opiniaModel.Opis);
                        sqlCmd.ExecuteNonQuery();
                    }
                }
                return(RedirectToAction("Index"));
            }
            else
            {
                return(View(opiniaModel));
            }
        }
        public ActionResult Edit(int id)
        {
            OpiniaModel opiniaModel = new OpiniaModel();
            DataTable   dtOpinia    = new DataTable();
            string      nameUser    = User.Identity.Name;

            using (SqlConnection sqlCon = new SqlConnection(connectionString))
            {
                sqlCon.Open();

                string     query  = "SELECT id FROM KONTO WHERE login_user=@UserName";
                SqlCommand sqlCmd = new SqlCommand(query, sqlCon);
                sqlCmd.Parameters.AddWithValue("@UserName", nameUser);
                int idCurrentUser = Convert.ToInt32(sqlCmd.ExecuteScalar());

                query = "select opis from opinia p INNER JOIN klient k " +
                        "ON p.klient_id = k.id INNER JOIN KONTO ko " +
                        "ON ko.id = k.konto_id WHERE ko.id = @KlientID and p.pracownik_id=@PracownikID;";
                SqlDataAdapter sqlDa = new SqlDataAdapter(query, sqlCon);
                sqlDa.SelectCommand.Parameters.AddWithValue("@PracownikID", id);
                sqlDa.SelectCommand.Parameters.AddWithValue("@KlientID", idCurrentUser);

                sqlDa.Fill(dtOpinia);
            }

            if (dtOpinia.Rows.Count == 1)
            {
                opiniaModel.Opis = dtOpinia.Rows[0][0].ToString();

                return(View(opiniaModel));
            }
            else if (dtOpinia.Rows.Count == 0)
            {
                opiniaModel.Opis = "Dodaj opinie...";

                return(View(opiniaModel));
            }
            else
            {
                return(RedirectToAction("Index"));
            }
        }