泛型实现List(ListT)排序

 public class Post : IComparable<Post>
{
    private string id = string.Empty;
    private string title = string.Empty;
    private int orderby;

    public string ID
    {
        get
        {
            return id;
        }
        set
        {
            id = value;
        }
    }
    public string Title
    {
        get
        {
            return title;
        }
        set
        {
            title = value;
        }
    }
    public int OrderBy
    {
        get
        {
            return orderby;
        }
        set
        {
            orderby = value;
        }
    }

    #region IComparable<Post> 成员

    public int CompareTo(Post other)
    {
        return ( orderby- other.orderby);
    }

    #endregion
}

让类继承IComparable接口，并且实现接口，在实现接口方法中设置为顺序排序

 

#region IComparable<Post> 成员

    public int CompareTo(Post other)
    {
        return ( orderby- other.orderby);
    }

  #endregion

 

倒序可以设置为

 

#region IComparable<Post> 成员

    public int CompareTo(Post other)
    {
        return ( other.orderby- orderby);
    }

    #endregion

 

默认实现泛型类型排序可以是使用List<T>.Sort()比如

 

        List<Post> posts = new List<Post>();
        for (int i = 0; i < 10; i++)
        {
            Post post = new Post();
            post.ID = i.ToString();
            post.Title = "哈哈";
            post.OrderBy = i;
            posts.Add(post);
        }
        //排序
        posts.Sort();
        foreach (Post p in posts)
        {
            Response.Write(p.ID + "<br>");
        }

 

我们可以看到输出的结果

0

1

.

.

.

10

如果我们其它属性排序比如ID,TITLE则如何实现？

 

 List<Post> posts = new List<Post>();
        for (int i = 0; i < 10; i++)
        {
            Post post = new Post();
            post.ID = i.ToString();
            post.Title = "哈哈";
            post.OrderBy = i;
            posts.Add(post);
        }
        //排序
        //posts.Sort();
        posts.Sort(delegate(Post p1, Post p2)
            {
                return p2.ID.CompareTo(p1.ID);
            }
        );
        foreach (Post p in posts)
        {
            Response.Write(p.ID + "<br>");
        }