c# - 分配 SQL Server 数据库记录而不是静态数据

Question

我在城市列表代码块中分配了静态数据，我在其中绑定(bind)了静态数据，例如:

country="Sri Lanka", 
city="Colombo", 
latitude= Convert.ToDecimal(79.861243), 
city_id= 4740, 
longitude= Convert.ToDecimal(79.861243)

但我想从 SQL Server 数据库表中分配数据。有人可以指导我如何分配 country = sql_data_reader["country"].ToString()，SQL Server 数据行替换静态数据。

public void GetCities()
{
            try
            {
                SqlConnection sql_con = new SqlConnection("Data Source=Mirzan;Initial Catalog=Numbeo_API;Integrated Security=True");
                string sql_query = "SELECT * FROM  Numbeo_API.dbo.cities";
                sql_con.Open();

                SqlCommand sql_command = new SqlCommand(sql_query, sql_con);
                SqlDataReader sql_data_reader = sql_command.ExecuteReader();

                List<City> city_list = new List<City>();

                while (sql_data_reader.Read())
                {
                    city_list.Add(new City
                    {
                        country = sql_data_reader["country"].ToString(),
                        city = sql_data_reader["city"].ToString(),
                        latitude = Convert.ToDecimal(sql_data_reader["latitude"]),
                        city_id = Convert.ToInt32(sql_data_reader["city_id"]),
                        longitude = Convert.ToDecimal(sql_data_reader["longitude"]),
                    });

                    foreach (var loop in city_list)
                    {
                        loop.country = sql_data_reader["country"].ToString();
                        loop.city = sql_data_reader["city"].ToString();
                        loop.latitude = Convert.ToDecimal(sql_data_reader["latitude"]);
                        loop.city_id = Convert.ToInt32(sql_data_reader["city_id"]);
                        loop.longitude = Convert.ToDecimal(sql_data_reader["longitude"]);
                    }
                }
            }
            catch (Exception ex)
            {
            }
        }

        private List<City> cities = new List<City>()
        {
            new City() {  country="Sri Lanka", city="Colombo", latitude= Convert.ToDecimal(79.861243), city_id= 4740, longitude=  Convert.ToDecimal(79.861243)}, 
            new City() { country="India", city="Mumbai", latitude= Convert.ToDecimal(19.075983), city_id= 4040, longitude=  Convert.ToDecimal(72.877655)}, 
            new City() { country="Sri Lanka", city="Galle", latitude= Convert.ToDecimal(6.230845), city_id= 4744, longitude=  Convert.ToDecimal(80.187506)}, 
            new City() { country="Sri Lanka", city="Matara", latitude= Convert.ToDecimal(5.949305), city_id= 4769, longitude=  Convert.ToDecimal(80.535347)},
            new City() {  country="Sri Lanka", city="Kurunagala", latitude= Convert.ToDecimal(5.949305), city_id= 4769,  longitude=  Convert.ToDecimal(80.535347) },
        };
    }
}

Answer 1

请删除 foreach 循环，因为它不是必需的。

并在您想要显示数据的地方使用您的 list.property。