C# -如何从数据库连接和查询并返回JsonResult

using System.Data.SqlClient;

string connectionString = "Data Source=数据库服务器地址;Initial Catalog=数据库名称;User ID=用户名;Password=密码";
SqlConnection connection = new SqlConnection(connectionString);
connection.Open();

using Newtonsoft.Json;

string query = "SELECT * FROM 表名";
SqlCommand command = new SqlCommand(query, connection);
SqlDataReader reader = command.ExecuteReader();

var result = new List<Dictionary<string, object>>();
while (reader.Read())
{
    var row = new Dictionary<string, object>();
    for (int i = 0; i < reader.FieldCount; i++)
    {
        row[reader.GetName(i)] = reader.GetValue(i);
    }
    result.Add(row);
}

string jsonResult = JsonConvert.SerializeObject(result);

using System.Web.Mvc;

return new JsonResult
{
    Data = jsonResult,
    JsonRequestBehavior = JsonRequestBehavior.AllowGet
};