using System;

​

public class Program

{

    public interface IDataContextFactory

    {

        string GetName();

    }

​

    public class UnitOfWork

    {

        private readonly IDataContextFactory repositoryFactory;

        public UnitOfWork(IDataContextFactory repositoryFactory)

        {

            this.repositoryFactory = repositoryFactory;

        }

        public string GetName()

        {

            return this.repositoryFactory.GetName();

        }

    }

​

    public class DataContextFactory : IDataContextFactory

    {

        public string GetName()

        {

            return "Tony";

        }

​

    }

    public class TestDataContextFactory : IDataContextFactory

    {

        public string GetName()

        {

            return "Test";

        }

​

        public object CreatePayrollDataContext()

        {

            return null;

        }

    }

​

​

    public static void Main()

    {

        var dcFactory = new TestDataContextFactory();

        var unitOfWork = new UnitOfWork(dcFactory);

        Console.WriteLine(unitOfWork.GetName());

    }

}