IQueryable定义一个扩展方法。分页

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;



namespace page

{

    public class PagedList<T> : List<T>

    {

        public PagedList(IEnumerable<T> content, int currentPage, int pageSize, int totalCount)

            : this(totalCount, currentPage, pageSize)

        {

            AddRange(content);

        }

        public PagedList(IQueryable<T> source, int currentPage, int pageSize)

            : this(source.Count(), currentPage, pageSize)

        {

            AddRange(source.Skip((CurrentPage - 1) * PageSize).Take(PageSize).ToList());

        }



        public PagedList(IEnumerable<T> source, int currentPage, int pageSize)

            : this(source.Count(), currentPage, pageSize)

        {

            AddRange(source.Skip((CurrentPage - 1) * PageSize).Take(PageSize).ToList());

        }



        protected PagedList(int count, int currentPage, int pageSize)

        {

            TotalCount = count;

            PageSize = Math.Max(pageSize, 1);

            CurrentPage = Math.Min(Math.Max(currentPage, 1), TotalPages);

        }



        public int CurrentPage { get; set; }



        public bool HasPreviousPage

        {

            get { return CurrentPage > 1; }

        }



        public bool HasNextPage

        {

            get { return CurrentPage < TotalPages; }

        }



        public int PageSize { get; set; }



        public int TotalCount { get; set; }



        public int TotalPages

        {

            get { return Math.Max((TotalCount + PageSize - 1) / PageSize, 1); }

        }

    }

}