using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

​

​

​

class Action 

{

public Guid ActionId { get;set;}

    public Guid OwnerId { get; set; }

    public virtual Contact Owner { get; set; }

    public string Title { get;set; }

}

​

static class ContextFactory {

public static DataContext NewReadonlyDataContext() => null;

}

​

​

class Contact 

{

    public string Name { get;set;}

    public Guid ContactId { get;}

}

​

class Before

{

    DataContext DataContext { get; }

    public string GetOwnerName(Guid actionId)

    {

        Action action = null;

        using(var dc = ContextFactory.NewReadonlyDataContext())

        {

            action = dc.Actions.First(x => x.ActionId == actionId);

        }

        return action.Owner.Name;

    }

    public void WriteActionsFor(Contact owner)

    {

        var actions = DataContext.Actions.Where(x => x.OwnerId == owner.ContactId)

            .ToList();

        foreach(var a in actions)

        {

            WriteActionData(a);

        }

    }

    public void WriteActionData(Action a) 

    {

        Response.Write(a.Title);

    }

}

​

​

public static class Response {

public static void Write(string x){}

}

​

class After 

{

    DataContext DataContext { get; }

    public void WriteActionsFor(Contact owner)

    {

        var actions = DataContext.Actions.Where(x => x.OwnerId == owner.ContactId)

            .Select(x => x.Title)

            .ToList();

        foreach(var a in actions)

        {

            WriteActionData(a);

        }

    }

    public void WriteActionData(string aTitle) 

    {

        Response.Write(aTitle);

    }

}

​

class DataContext : IDisposable {

    public IQueryable<Action> Actions { get; }

    public void Dispose() {}

}