分页类

 

/// <summary>

    ///     分页

    /// </summary>

    /// <typeparam name="T">类型</typeparam>

    public class PagedList<T> : List<T>

    {

        /// <summary>

        ///     缓存分页构造函数

        /// </summary>

        /// <param name="source">数据源</param>

        /// <param name="pageIndex">当前页页码</param>

        /// <param name="pageSize">每页显示记录数</param>

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

        {

            if (source == null || !source.Any())

                throw new ArgumentNullException("source");



            int total = source.Count();

            TotalCount = total;

            TotalPages = total/pageSize;



            if (total%pageSize > 0)

                TotalPages++;



            PageSize = pageSize;

            PageIndex = pageIndex;

            AddRange(source.Skip(pageIndex*pageSize).Take(pageSize).ToList());

        }



        /// <summary>

        ///     缓存分页构造函数

        /// </summary>

        /// <param name="source">数据源</param>

        /// <param name="pageIndex">当前页页码</param>

        /// <param name="pageSize">每页显示记录数</param>

        public PagedList(IList<T> source, int pageIndex, int pageSize)

        {

            if (source == null || !source.Any())

                throw new ArgumentNullException("source");



            TotalCount = source.Count();

            TotalPages = TotalCount/pageSize;



            if (TotalCount%pageSize > 0)

                TotalPages++;



            PageSize = pageSize;

            PageIndex = pageIndex;

            AddRange(source.Skip(pageIndex*pageSize).Take(pageSize).ToList());

        }



        /// <summary>

        ///     非缓存分页构造函数

        /// </summary>

        /// <param name="source">数据源</param>

        /// <param name="pageIndex">当前页页码</param>

        /// <param name="pageSize">每页显示记录数</param>

        /// <param name="totalCount">总记录数</param>

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

        {

            if (source == null || !source.Any())

                throw new ArgumentNullException("source");



            TotalCount = totalCount;

            TotalPages = TotalCount/pageSize;



            if (TotalCount%pageSize > 0)

                TotalPages++;



            PageSize = pageSize;

            PageIndex = pageIndex;

            AddRange(source);

        }



        /// <summary>

        ///     当前页页码

        /// </summary>

        public int PageIndex { get; private set; }



        /// <summary>

        ///     每页显示记录数

        /// </summary>

        public int PageSize { get; private set; }



        /// <summary>

        ///     总记录数

        /// </summary>

        public int TotalCount { get; private set; }



        /// <summary>

        ///     总页数

        /// </summary>

        public int TotalPages { get; private set; }



        /// <summary>

        ///     有上一页

        /// </summary>

        public bool HasPreviousPage

        {

            get { return (PageIndex > 0); }

        }



        /// <summary>

        ///     有下一页

        /// </summary>

        public bool HasNextPage

        {

            get { return (PageIndex + 1 < TotalPages); }

        }

    }