castle实例分析（二）

HasMany--表示一对多的关系

Posts 的blogid是blogs表的外键，可以在blog类中设置HasMany属性，使blog类有一系列的Posts

using Castle.ActiveRecord;
 [ActiveRecord("blogs")]
public class Blog : ActiveRecordBase
{
    private int id;
    private string name;
    private IList posts = new ArrayList();
    [PrimaryKey]
    public int Id
    {
        get { return id; }
        set { id = value; }
    }
    [Property]
    public string Name
    {
        get { return name; }
        set { name = value; }
    }
    [HasMany(typeof(Post), Table="Posts", ColumnKey="blogid")，
 Inverse=true, Cascade=ManyRelationCascadeEnum.AllDeleteOrphan)]
    public IList Posts
    {
        get { return posts; }
        set { posts = value; }
    }
}
注意：如果另一边有关联的类(Post类)有BelongsTo关联blog类，可以省略Table和ColumnKey 属性

使用示例：
Blog blog = new Blog();
blog.Name = "hammett's blog";
blog.Create();
Post post = new Post();
post.Title = "First post";
post.Contents = "Hello world";
post.Create();
blog.Posts.Add(post);
blog.Update();