自定义分页控件PageList

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace Commons
{
    public class PageList<T> : IEnumerable<T>
    {
        private int pageIndex;
        private int pageSize;
        private int totalPage;
        private int totalCount;

        private IList<T> list;

        /// <summary>
        /// 单页数据，总条数，计算出总页数，然后封装成分页对象
        /// </summary>
        /// <param name="list"></param>
        /// <param name="pageIndex"></param>
        /// <param name="pageSize"></param>
        /// <param name="totalCount"></param>
        public PageList(IList<T> list, int pageIndex, int pageSize, int totalCount)
        {
            if (list != null)
            {
                this.pageIndex = pageIndex;
                this.pageSize = pageSize;
                this.totalCount = totalCount;
                this.totalPage = totalCount / pageSize;
                if (totalCount % pageSize > 0) this.totalPage += 1;

                this.list = list;
            }
            else
            {
                this.list = new List<T>();
            }
        }
        /// <summary>
        /// 全部数据，筛选出当页数据且计算出总条数和总页数，然后封装成分页对象
        /// </summary>
        /// <param name="list"></param>
        /// <param name="pageIndex"></param>
        /// <param name="pageSize"></param>
        public PageList(IList<T> list, int pageIndex, int pageSize)
        {
            if (list != null)
            {
                this.pageIndex = pageIndex;
                this.pageSize = pageSize;
                this.totalCount = list.Count;
                this.totalPage = list.Count / pageSize;
                if (list.Count % pageSize > 0) this.totalPage += 1;

                this.list = list.Skip(pageSize * (pageIndex - 1)).Take(pageSize).ToList();
            }
            else
            {
                this.list = new List<T>();
            }
        }
        public int PageIndex { get { return this.pageIndex; } }
        public int PageSize { get { return this.pageSize; } }
        public int TotalPage { get { return this.totalPage; } }
        public int TotalCount { get { return this.totalCount; } }

        public IEnumerator<T> GetEnumerator()
        {
            foreach (var item in this.list)
            {
                yield return item;
            }
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            throw new NotImplementedException();
        }

        public IHtmlString PageBar(string url, object property)
        {
            if (string.IsNullOrEmpty(url)) url = string.Empty;
            else
            {
                url = url.Trim().TrimEnd('?', '&');
                if (url.Contains("?")) url += "&";
                else url += "?";
            }
            string html = "<ul class=\"pagination\">{0}</ul>";
            int pageMin = 1, pageMax = this.TotalPage;
            string page = string.Empty;
            for (int i = this.PageIndex - 1; (i > (this.PageIndex - 5)) && i > 0; i--)
            {
                string pageUrl = string.Format("{0}pageIndex={1}", url, i);
                page = "<li><a href=\"" + pageUrl + "\">" + i + "</a></li>" + page;
                pageMin = i;
            }
            page = page + "<li class=\"active\"><a href=\"#\">" + this.pageIndex + "</a></li>";
            for (int i = this.PageIndex + 1; (i < (this.PageIndex + 5)) && i < this.TotalPage + 1; i++)
            {
                string pageUrl = string.Format("{0}pageIndex={1}", url, i);
                page = page + "<li><a href=\"" + pageUrl + "\">" + i + "</a></li>";
                pageMax = i;
            }
            //第一页和最后一页
            if (pageMin > 1)
            {
                if ((pageMin - 1) > 1)
                    page = "<li><a>...</a></li>" + page;
                string pageUrl = string.Format("{0}pageIndex={1}", url, 1);
                page = "<li><a href=\"" + pageUrl + "\">" + 1 + "</a></li>" + page;
            }
            if (pageMax < this.TotalPage)
            {
                if ((this.TotalPage - pageMax) > 1)
                    page = page + "<li><a>...</a></li>";
                string pageUrl = string.Format("{0}pageIndex={1}", url, this.TotalPage);
                page = page + "<li><a href=\"" + pageUrl + "\">" + this.TotalPage + "</a></li>";
            }
            //上一页和下一页
            if (this.pageIndex == 1)
                page = "<li class=\"prev disabled\"><a href=\"#\"><span class=\"fa fa-angle-left\"></span>&nbsp;上一页</a></li>" + page;
            else
                page = "<li class=\"prev\"><a href=\"" + string.Format("{0}pageIndex={1}", url, this.pageIndex - 1) + "\"><span class=\"fa fa-angle-left\"></span>&nbsp;上一页</a></li>" + page;
            if (this.pageIndex == this.TotalPage)
                page = page + "<li class=\"next disabled\"><a href=\"#\">下一页&nbsp;<span class=\"fa fa-angle-right\"></span></a></li>";
            else
                page = page + "<li class=\"next\"><a href=\"" + string.Format("{0}pageIndex={1}", url, this.pageIndex + 1) + "\">下一页&nbsp;<span class=\"fa fa-angle-right\"></span></a></li>";
            html = string.Format(html, page);
            return new HtmlString(html);
        }
    }
}