using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

​

public class DataHelper<TConnection>

    where TConnection : System.Data.Common.DbConnection    

{

}

​

class DataNetFactory

{

    protected virtual void DataNetFacotry()

    {

        _dataExecutor = new DataHelper<System.Data.Common.DbConnection>();

    }

​

    protected DataHelper<System.Data.Common.DbConnection> _dataExecutor;

}

​

class ODBCNetFactory : DataNetFactory

{

    public ODBCNetFactory()

    {

        _dataExecutor = new DataHelper<System.Data.Odbc.OdbcConnection>();

    }

​

}