using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Reflection;

namespace MCO.EF

{

    public class Test

    {

        //实例化上下文

        ConnectionSQL connection = new ConnectionSQL();

        //增加

        public int DataAdd()

        {

            User user = new User()

            {

                UserName = "陆六",

                UserSex = true

            };

            connection.User.Add(user);

            return connection.SaveChanges();

        }

        //删除

        public int Delete()

        {

            List<User> user = connection.User.Where<User>(u => u.UserId > ).ToList<User>();

            foreach(User u in user)

            {

                connection.User.Remove(u);

            }

            return connection.SaveChanges();

        }

        //修改

        public int Update()

        {

            List<User> user =  connection.User.Where<User>(u => u.UserSex == true).ToList<User>();

            foreach(User u in user)

            {

                u.UserSex = false;

            }

            return connection.SaveChanges();

        }

        //查询

        private void UserList()

        {

            IQueryable userList = connection.User.Where<User>(u => u.UserId > );

            //反射获取实体类的所有属性值和属性名

            PropertyInfo[] attribute = typeof(User).GetProperties();

            //调用 ListToJson 方法

            Console.Write(ListToJson(attribute, userList));

        }

        //反射拼接成 json

        private string ListToJson(PropertyInfo[] attribute, IQueryable dataList)

        {

            StringBuilder strJson = new StringBuilder();

            foreach(var data in dataList)

            {

                strJson.Append("{");

                for(int i = ; i < attribute.Length; i++)

                {

                    //获取属性名 和 属性值(通过反射)

                    strJson.AppendFormat("\"{0}\":\"{1}\",", attribute[i].Name, attribute[i].GetValue(data));

                }

                strJson.Remove(strJson.Length - , );

                strJson.Append("},");

            }

            strJson.Remove(strJson.Length - , );

            return strJson.ToString();

        }

    }

}