PhiHuyHoang

    interface RunMethod { void Go(); }
    class Car : RunMethod
    {
        public void Go()
        {
            Console.WriteLine("I'm driving");
        }
    }
    class Helicopter : RunMethod
    {

PhiHuyHoang

class Vehicle
    {
      public void Go()
          {
              Console.WriteLine("I'm driving");
          } 
    }

    class Car : Vehicle {}
    class Helicopter : Vehicle {}

PhiHuyHoang

class Program
    {
        static void Main(string[] args)
        {
            Me me = new Me();
            me.viewGirl();
            Console.ReadLine();
        }
    }

PhiHuyHoang

class Me
    {
        public void viewGirl()
        {
            GirlFactory girlFactory = new GirlFactory();
            girlFactory.checkGirl("Vietnam");
            girlFactory.checkGirl("Japan");
            girlFactory.checkGirl("China");
        }
    }

PhiHuyHoang

class GirlFactory
    {
        public void checkGirl(String national)
        {
            Girl girl;
            if(national.Equals("Vietnam"))
            {
                girl = new Vietnamese();
                girl.check();
            }

PhiHuyHoang

class Program
    {
        static void Main(string[] args)
        {
            Me me = new Me();
            me.viewVietnamGirl();
            me.viewChinaGirl();
            me.viewJapanGirl();
            Console.ReadLine();
        }

PhiHuyHoang

class Me
    {
        public void viewVietnamGirl()
        {
            Vietnamese v = new Vietnamese();
            v.check();
        }

        public void viewChinaGirl()
        {

PhiHuyHoang

public interface Girl
    {
        void check();
    }
    class Vietnamese : Girl
    {
        public void check()
        {
            Console.WriteLine("Girl from Vietnam");
        }

PhiHuyHoang

using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace linq_ORM_entities
{
    public static class CustomExtentions

PhiHuyHoang

 public static class ConsoleExtension
    {
        public static void ToConsole<T>(this IEnumerable<T> s, string header)
        {
            Console.WriteLine($"*********BEGIN {header}**************");
            foreach (T item in s)
            {
                Console.WriteLine(item);
            }
            Console.WriteLine($"*********END {header}**************");