c#延迟加载

public class BlogUser
{
public int Id { get; private set; }
public Lazy<List<Article>> Articles { get; private set; }
public BlogUser(int id)
{
this.Id = id;
Articles = new Lazy<List<Article>>(() => ArticleServices.GetArticesByID(id));
Console.WriteLine("BlogUser Initializer");
}

}

public class Article
{
public int Id { get; set; }
public string Title { get; set; }
public DateTime PublishDate { get; set; }
}

public class ArticleServices
{
public static List<Article> GetArticesByID(int blogUserID)
{
List<Article> articles = new List<Article> {
new Article{Id=1,Title="Lazy Load",PublishDate=DateTime.Parse("2011-4-20")},
new Article{Id=2,Title="Delegate",PublishDate=DateTime.Parse("2011-4-21")},
new Article{Id=3,Title="Event",PublishDate=DateTime.Parse("2011-4-22")},
new Article{Id=4,Title="Thread",PublishDate=DateTime.Parse("2011-4-23")}
};
Console.WriteLine("Article Initalizer");
return articles;
}
}

BlogUser blogUser = new BlogUser(1);
Console.WriteLine("blogUser has been initialized");

foreach (var article in blogUser.Articles.Value)
{
Console.WriteLine(article.Title);
}