#region my model

    [KnownType(typeof(model1))]
    [KnownType(typeof(model2))]
    [KnownType(typeof(model3))]
    public class TaskGroupObjects : List<IBaseObject>
    {
        #region sortFields
        class compare : IComparer<IBaseObject>
        {
            public int Compare(IBaseObjectfield1, IBaseObjectfield2)
            {
                return field1.Order - field2.Order;
            }
        }

        public void sortByOrder()
        {
            Sort(new compare());
        }
        #endregion
    }

public static bool HasProperty(this object your model, string propertyName)
{
    return obj.GetType().GetProperty(propertyName) != null;
}

 {
    "dependencies": {
      //same as before  
      "Microsoft.AspNetCore.Mvc": "1.0.0"
 },

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();

public void Configure(IApplicationBuilder app)
{
   app.UseFileServer();
   app.UseMvcWithDefaultRoute();

namespace Core1RtmEmptyTest.Controllers
{
    public class HomeController
    {
        public string Index()
        {
            return "Running a POCO controller!";
        }
    }
}

using Microsoft.AspNetCore.Mvc;
 
namespace Core1RtmEmptyTest.Controllers
{
    public class AboutController : Controller
    {
        public IActionResult Index()
        {
            return Content("Hello from DNT!");
        }
    }
}

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
 
namespace Core1RtmEmptyTest.Controllers
{
    public class HomeController
    {
        [ActionContext]
        public ActionContext ActionContext { get; set; }
 
        public HttpContext HttpContext => ActionContext.HttpContext;
 
        public string Index()
        {
            return "Running a POCO controller!";
        }
 
        public IActionResult About()
        {
            return new ContentResult
            {
                Content = "Hello from DNT!",
                ContentType = "text/plain; charset=utf-8"
            };
        }
    }
}

 string, int?, byte[]

 int, decimal, bool, DateTime

 [Required]
public string Url { get; set; }

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
   modelBuilder.Entity<Blog>()
              .Property(b => b.Url)
              .IsRequired();
}

public string FirstName { get; set; }

  [StringLength(450)]
  public string FirstName { get; set; }

  [MaxLength(450)]
  public string LastName { get; set; }

  [MaxLength]
  public string Address { get; set; }

modelBuilder.Entity<Person>()
   .Property(x => x.Address)
   .HasMaxLength(450);

modelBuilder.Entity<Person>()
   .Property(x => x.Address)
   .HasColumnType("nvarchar(max)");

   [Column(TypeName = "varchar")]
  [MaxLength]
  public string Address { get; set; }
 

 Data type 'varchar' is not supported in this form. Either specify the length explicitly in the type name, for example as 'varchar(16)',
or remove the data type and use APIs such as HasMaxLength to allow EF choose the data type.

   [Column(TypeName = "varchar(max)")]

    public class Person 
    {
        public int Id { set; get; }

        public DateTime? DateAdded { set; get; }

        public DateTime? DateUpdated { set; get; }

        [StringLength(450)]
        public string FirstName { get; set; }

        [MaxLength(450)]
        public string LastName { get; set; }

        //[Column(TypeName = "varchar")]
        [MaxLength]
        public string Address { get; set; }


        //bit
        public bool IsActive { get; set; }

        //tiny Int
        public byte Age { get; set; }

        //small Int
        public short Short { get; set; }

        //int
        public int Int32 { get; set; }

        //Big int
        public long Long { get; set; }
    }

 CREATE TABLE [dbo].[Persons](
 [DateAdded] [datetime2](7) NULL,
 [DateUpdated] [datetime2](7) NULL,

 [ConcurrencyCheck]
public string Name { set; get; }

modelBuilder.Entity<Person>()
    .Property(p => p.Name)
    .IsConcurrencyToken();

 [Timestamp]
 public byte[] Timestamp { get; set; }

modelBuilder.Entity<Blog>()
   .Property(p => p.Timestamp)
   .ValueGeneratedOnAddOrUpdate()
   .IsConcurrencyToken();

            // Get Customer Type from Customer click on Print Button
            int customerType = 0;

            // Create Object without instantiation
            object obj;


            //Instantiate obj according to customer Type
            if (customerType == 1)
            {
                obj = new Customer1();
            }
            else if (customerType == 2)
            {
                obj = new Customer2();
            }
            // Problem:
            //          1: Scattered New Keywords
            //          2: Client side is aware of Customer Type

namespace Interface
{
    public interface ICustomer
    {
        void Report();
    }
}

// Customer1
using System;
using Interface;

namespace MainClass
{
    public class Customer1 : ICustomer
    {
        public void Report()
        {           
            Console.WriteLine("این گزارش مخصوص مشتری نوع اول است");           
        }
    }
}

//Customer2
using System;
using Interface;

namespace MainClass
{
   public class Customer2 : ICustomer
    {
        public void Report()
        {           
            Console.WriteLine("این گزارش مخصوص مشتری نوع دوم است");           
        }
    }
}

//Factory
using System;
using Interface;
using MainClass;

namespace FactoryClass
{
    public class clsFactory
    {
        static public ICustomer getCustomerType(int intCustomerType)
        {
            ICustomer objCust;
            if (intCustomerType == 1)
            {
                objCust = new Customer1();
            }
            else if (intCustomerType == 2)
            {
                objCust = new Customer2();
            }
            else
            {
                return null;
            }
            return objCust;
        }
    }
}

//UI (Client)
using System;
using FactoryClass;
using Interface;

namespace DesignPattern
{
    class Program
    {
        static void Main(string[] args)
        {
            int intCustomerType = 0;
            ICustomer objCust;
            Console.WriteLine("نوع مشتری را وارد نمایید");           
            intCustomerType = Convert.ToInt16(Console.ReadLine());
            objCust = clsFactory.getCustomerType(intCustomerType);
            objCust.Report();
            Console.ReadLine();
        }
    }
}

public class CirclePreview:IPeiview
    {
        private readonly Graphics graphics;

        public CirclePreview(Graphics graphics)
        {
            this.graphics = graphics;
        }
        public void Draw(ShapeSpecification shapeScepification)
        {
            var startPoints = AreaParser.Parse(shapeScepification.StartPoint, shapeScepification.EndPoint);

            float raduis = Math.Max(startPoints.Width, startPoints.Height);

            if (shapeScepification.IsFill)
                this.graphics.FillEllipse(shapeScepification.BackgroundBrush, startPoints.XPoint, startPoints.YPoint, raduis, raduis);
            else
                this.graphics.DrawEllipse(new Pen(shapeScepification.ForeColor, shapeScepification.Thickness), startPoints.XPoint, startPoints.YPoint, raduis, raduis);
        }
    }

using System;
using System.Reflection;
using PostSharp.Aspects;

namespace AOP03
{
    public class ApplicationExceptionHandlerAspect : OnExceptionAspect
    {
        public override void OnException(MethodExecutionArgs args)
        {
            Console.WriteLine("Exception Type: {0}, StackTrace: {1}",
                               args.Exception.GetType().Name,
                               args.Exception.StackTrace);
        }

        public override Type GetExceptionType(MethodBase targetMethod)
        {
            return typeof(ApplicationException);
        }
    }
}

using System;
using PostSharp.Aspects;

namespace AOP03
{
    public class ObjectInitializationAspect : LocationInterceptionAspect
    {
        public override void OnGetValue(LocationInterceptionArgs args)
        {
            if (args.GetCurrentValue() == null)
            {
                Console.WriteLine("Property {0} is null.", args.LocationFullName);
            }
        }
    }
}

using PostSharp.Aspects;
using System;

namespace AOP03
{
    public class LogEventAspect : EventInterceptionAspect
    {
        public override void OnAddHandler(EventInterceptionArgs args)
        {
            Console.WriteLine("Event {0} added", args.Event.Name);
            args.ProceedAddHandler();
        }

        public override void OnRemoveHandler(EventInterceptionArgs args)
        {
            Console.WriteLine("Event {0} removed", args.Event.Name);
            args.ProceedRemoveHandler();
        }

        public override void OnInvokeHandler(EventInterceptionArgs args)
        {
            Console.WriteLine("Event {0} invoked", args.Event.Name);
            args.ProceedInvokeHandler();
        }
    }
}

    public class LoggingAspect : OnMethodBoundaryAspect
    {
        public override bool CompileTimeValidate(System.Reflection.MethodBase method)
        {
            return !method.IsStatic;
        }