using System;

using System.Reflection;

internal interface IInternalInterface

{

    bool Flag { get; set; }

}

public class InterfaceImplementation : IInternalInterface

{

    public bool PublicFlag { get; set; }

​

    bool IInternalInterface.Flag { get; set; }

}

​

public class Program

{

    public static void Main()

    {

        var type = typeof(InterfaceImplementation);

        var properties = type.GetProperties();

        foreach (var property in properties)

        {

            Console.WriteLine(property.Name);

        }

    }

}