var comments=new PagedList<Comment>(  ((IEnumerable<Comment>)db.ExecuteQuery<Comment>(StrSql) ).ToList(),pageIndex,pageSize,totalCount)

    public class PagedList<T> : List<T>,IPagedList
    {
        public PagedList(IEnumerable<T> items, int pageIndex, int pageSize, int totalItemCount)
        {
            AddRange(items);
            TotalItemCount = totalItemCount;
            CurrentPageIndex = pageIndex;
            PageSize = pageSize;
        }

        public int CurrentPageIndex { get; set; }
        public int PageSize { get; set; }
        public int TotalItemCount { get; set; }
        public int TotalPageCount { get { return (int)Math.Ceiling(TotalItemCount / (double)PageSize); } }
        public int StartRecordIndex { get { return (CurrentPageIndex - 1) * PageSize + 1; } }
        public int EndRecordIndex { get { return TotalItemCount > CurrentPageIndex * PageSize ? CurrentPageIndex * PageSize : TotalItemCount; } }
    }