BlogPost3_Service_Example.cs

public class BlogPost
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
    public bool Disabled { get; set; }
    public DateTime Created { get; set; }
}

public interface IBlogService
{
    void DisablePost(BlogPost post);
    BlogPost GetPost(int id);
}

public class BlogService : IBlogService
{
    public BlogPost GetPost(int id)
    {
        return new BlogPost
        {
            Id = id,
            Title = "Test",
            Description = "Test",
            Disabled = false,
            Created = DateTime.UtcNow
        };
    }

    public void DisablePost(BlogPost post)
    {
        post.Disabled = true;
    }
}