Page.cs

using System;
using System.Collections.Generic;

/// <summary>
/// 分页类
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
public class Page<T> : IEnumerable<T>
{
    /// <summary>
    /// 创建一个分页类
    /// </summary>
    /// <param name="list">当前页列表</param>
    /// <param name="totalCount">分页总个数</param>
    /// <param name="pageIndex">当前页数</param>
    public Page(List<T> list, int pageIndex, int pageSize, int totalCount, int pageLabelCount)
    {
        PageIndex = pageIndex;
        TotalCount = totalCount;
        List = list;
        PageLabelCount = pageLabelCount;
        PageSize = pageSize;
    }

    private int pageSize;

    /// <summary>
    /// 每页显示数量
    /// </summary>
    public int PageSize { get { return pageSize; } set { if (value > 0) pageSize = value; else pageSize = 1; } }

    public int PrePage
    {
        get
        {
            return pageIndex > 1 ? pageIndex - 1 : 1;

        }
    }

    public int NextPage {
        get {
            return pageIndex >= TotalPage ? TotalPage : pageIndex + 1;
        }
    }

    private int pageIndex = 1;
    /// <summary>
    /// 当前页数
    /// </summary>
    public int PageIndex
    {
        get
        {
            return pageIndex;
        }

        set
        {
            if (value >= 1)
            {
                pageIndex = value;
            }
        }
    }


    private int totalCount;
    /// <summary>
    /// 最大个数
    /// </summary>
    public int TotalCount
    {
        get
        {
            return totalCount;
        }
        set
        {
            totalCount = value < 0 ? 0 : value;
        }
    }

    /// <summary>
    /// 当前页面列表
    /// </summary>
    public List<T> List { get; set; }

    /// <summary>
    /// 最大页数
    /// </summary>
    public int TotalPage
    {
        get
        {
            return (int)Math.Ceiling(TotalCount / (double)PageSize) <= 0 ? 1 : (int)Math.Ceiling(TotalCount / (double)PageSize);
        }
    }

    private int pageLabelCount = 5;
    /// <summary>
    /// 页标个数
    /// </summary>
    public int PageLabelCount
    {
        get { return pageLabelCount; }
        set { pageLabelCount = value <= 0 ? 1 : value; }
    }

    /// <summary>
    /// 取得页标列表
    /// </summary>
    /// <returns></returns>
    public int[] GetPageLabel()
    {
        PageIndex = PageIndex > TotalPage ? TotalPage : PageIndex;

        if (pageLabelCount == 1)
        {
            return new int[] { PageIndex };
        }

        List<int> list = new List<int>();
        int startPage = 0;
        int endPage = 0;

        if (PageLabelCount == 2)
        {
            startPage = PageIndex == TotalPage ? PageIndex - 1 : PageIndex;
            startPage = startPage < 1 ? 1 : startPage;

            endPage = startPage + 1;
            endPage = endPage > TotalPage ? TotalPage : endPage;
        }
        else if (PageLabelCount % 2 == 0)
        {

            int labelPage = (int)Math.Floor((PageIndex - 2) / (double)(PageLabelCount - 2)) + 1;

            startPage = (labelPage - 1) * (PageLabelCount - 2) + 1;

            startPage = startPage < 1 ? 1 : startPage;
            startPage = startPage > TotalPage ? TotalPage : startPage;

            endPage = startPage + PageLabelCount - 1;
            endPage = endPage > TotalPage ? TotalPage : endPage;
            endPage = endPage < 1 ? 1 : endPage;
        }
        else
        {
            startPage = PageIndex - ((PageLabelCount - 1) / 2);
            startPage = startPage < 1 ? 1 : startPage;
            startPage = startPage > TotalPage ? TotalPage : startPage;

            endPage = startPage + PageLabelCount - 1;
            endPage = endPage > TotalPage ? TotalPage : endPage;
            endPage = endPage < 1 ? 1 : endPage;
        }

        for (int i = startPage; i <= endPage; i++)
        {
            list.Add(i);
        }

        return list.ToArray();
    }

    public IEnumerator<T> GetEnumerator()
    {
        return List.GetEnumerator();
    }

    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        return List.GetEnumerator();
    }
}