sharepoint多表查询

   private static PagedDataSource pds = new PagedDataSource();
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
               
                BindData();
             }
        }
        private void BindData()
        {
          //  var ForumBox = SharePointUtility.GetListItemDictionary<IT论坛>("IT_Forums");
            //IEnumerable<IT论坛> LeaderMail = ForumBox.Values
                            //    .OrderByDescending(item => item.创建时间);
            var ForumBoxData = this.GetSiteData().ForumBox.Values;
            var ForumClickBoxData = this.GetSiteData().ForumClickBox.Values;
            var LeaderMail = (from f in ForumBoxData  
                              join fc in ForumClickBoxData on f.ID equals fc.IT_ID into temp
                              from tt in temp.DefaultIfEmpty()
                              orderby f.创建时间 descending
                              select new { ID=f.ID,Url路径=f.Url路径,创建者=f.创建者,主题=f.主题,答复=f.答复,点击量= tt==null?0:tt.点击量,创建时间=f.创建时间}).ToList();
            int mailcount = LeaderMail.Count();
            if (mailcount <= 0)
            {
                Label1.Text = "暂无数据";
            }
            else
            {
                Label1.Text = "";
            }
            AspNetPager.RecordCount = mailcount;
            AspNetPager.PageSize = 20;

            //pds.DataSource = LeaderMail.ToList();
            pds.DataSource = LeaderMail;
            pds.AllowPaging = true; //数据源  允许分页
            pds.CurrentPageIndex = AspNetPager.CurrentPageIndex - 1; //显示 当前页  
            pds.PageSize = AspNetPager.PageSize; //取控件 分页大小  
            BindToList();
        }
        private void BindToList()
        {
            rpt_List.DataSource = pds;
            rpt_List.DataBind();
            
        }
        protected void AspNetPager_PageChanged(object src, EventArgs e)
        {
            pds.CurrentPageIndex = AspNetPager.CurrentPageIndex - 1; //显示 当前页  
            pds.PageSize = AspNetPager.PageSize; //取控件 分页大小  
            BindToList();
        }