• access下的分页方案(仿sql存储过程)


    using System;
    using System.Collections.Generic;
    using System.Text;
    using System.Data;
    using System.Data.OleDb;
    using System.Web;

    /**//// <summary>
    /// 名称:access下的分页方案(仿sql存储过程)
    /// 作者:cncxz(虫虫)
    /// blog:
    http://cncxz.cnblogs.com
    /// </summary>
    public class AdoPager
    {
        protected string m_ConnString;
        protected OleDbConnection m_Conn;

        public AdoPager()
        {
            CreateConn(string.Empty);
        }
        public AdoPager(string dbPath)
        {
            CreateConn(dbPath);
        }

        private void CreateConn(string dbPath)
        {
            if (string.IsNullOrEmpty(dbPath))
            {
                string str = System.Configuration.ConfigurationManager.AppSettings["dbPath"] as string;
                if (string.IsNullOrEmpty(str))
                    str = "~/App_Data/db.mdb";
                m_ConnString = string.Format(@"Provider=Microsoft.Jet.OLEDB.4.0;Data source={0}", HttpContext.Current.Server.MapPath(str));
            }
            else
                m_ConnString = string.Format(@"Provider=Microsoft.Jet.OLEDB.4.0;Data source={0}", dbPath);

            m_Conn = new OleDbConnection(m_ConnString);
        }
        /**//// <summary>
        /// 打开连接
        /// </summary>
        public void ConnOpen()
        {
            if (m_Conn.State != ConnectionState.Open)
                m_Conn.Open();
        }
        /**//// <summary>
        /// 关闭连接
        /// </summary>
        public void ConnClose()
        {
            if (m_Conn.State != ConnectionState.Closed)
                m_Conn.Close();
        }

        private string recordID(string query, int passCount)
        {
            OleDbCommand cmd = new OleDbCommand(query, m_Conn);
            string result = string.Empty;
            using (IDataReader dr = cmd.ExecuteReader())
            {
                while (dr.Read())
                {
                    if (passCount < 1)
                    {
                        result += "," + dr.GetInt32(0);
                    }
                    passCount--;
                }
            }
            return result.Substring(1);
        }


        /**//// <summary>
        /// 获取当前页应该显示的记录,注意:查询中必须包含名为ID的自动编号列,若不符合你的要求,就修改一下源码吧 :)
        /// </summary>
        /// <param name="pageIndex">当前页码</param>
        /// <param name="pageSize">分页容量</param>
        /// <param name="showString">显示的字段</param>
        /// <param name="queryString">查询字符串,支持联合查询</param>
        /// <param name="whereString">查询条件,若有条件限制则必须以where 开头</param>
        /// <param name="orderString">排序规则</param>
        /// <param name="pageCount">传出参数:总页数统计</param>
        /// <param name="recordCount">传出参数:总记录统计</param>
        /// <returns>装载记录的DataTable</returns>
        public DataTable ExecutePager(int pageIndex, int pageSize, string showString, string queryString, string whereString, string orderString, out int pageCount, out int recordCount)
        {
            if (pageIndex < 1) pageIndex = 1;
            if (pageSize < 1) pageSize = 10;
            if (string.IsNullOrEmpty(showString)) showString = "*";
            if (string.IsNullOrEmpty(orderString)) orderString = "ID desc";
            ConnOpen();
            string myVw = string.Format(" ( {0} ) tempVw ", queryString);
            OleDbCommand cmdCount = new OleDbCommand(string.Format(" select count(0) as recordCount from {0} {1}", myVw, whereString), m_Conn);

            recordCount = Convert.ToInt32(cmdCount.ExecuteScalar());

            if ((recordCount % pageSize) > 0)
                pageCount = recordCount / pageSize + 1;
            else
                pageCount = recordCount / pageSize;
            OleDbCommand cmdRecord;
            if (pageIndex == 1)//第一页
            {
                cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, whereString, orderString), m_Conn);
            }
            else if (pageIndex > pageCount)//超出总页数
            {
                cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, "where 1=2", orderString), m_Conn);
            }
            else
            {
                int pageLowerBound = pageSize * pageIndex;
                int pageUpperBound = pageLowerBound - pageSize;
                string recordIDs = recordID(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageLowerBound, "ID", myVw, whereString, orderString), pageUpperBound);
                cmdRecord = new OleDbCommand(string.Format("select {0} from {1} where id in ({2}) order by {3} ", showString, myVw, recordIDs, orderString), m_Conn);

            }
            OleDbDataAdapter dataAdapter = new OleDbDataAdapter(cmdRecord);
            DataTable dt=new DataTable();
            dataAdapter.Fill(dt);
            ConnClose();
            return dt;
        }
    }

    还有调用示例:html代码

    <%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

    <html xmlns="http://www.w3.org/1999/xhtml" >
    <head runat="server">
        <title>分页演示</title>
    </head>
    <body>
        <form id="form1" runat="server">
        <div>
            <br />
            &nbsp; 转到第<asp:TextBox ID="txtPageSize" runat="server" Width="29px">1</asp:TextBox>页<asp:Button ID="btnJump" runat="server" Text="Go" OnClick="btnJump_Click" /><br />
            <asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333" GridLines="None" Width="90%">
                <FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                <RowStyle BackColor="#EFF3FB" />
                <EditRowStyle BackColor="#2461BF" />
                <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
                <PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
                <HeaderStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                <AlternatingRowStyle BackColor="White" />
            </asp:GridView>
        
        </div>
            <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
        </form>
    </body>
    </html>

    示例的codebehind代码

    using System;
    using System.Data;
    using System.Configuration;
    using System.Web;
    using System.Web.Security;
    using System.Web.UI;
    using System.Web.UI.WebControls;
    using System.Web.UI.WebControls.WebParts;
    using System.Web.UI.HtmlControls;
    using System.Collections.Generic;

    public partial class _Default : System.Web.UI.Page 
    {
        private AdoPager mm_Pager;
        protected AdoPager m_Pager
        { 
            get{
                if (mm_Pager == null)
                    mm_Pager = new AdoPager();
                return mm_Pager;
            }
        }
        protected void Page_Load(object sender, EventArgs e)
        {
            if(!IsPostBack)
                LoadData();
        }
        private int pageIndex = 1;
        private int pageSize = 20;
        private int pageCount = -1;
        private int recordCount = -1;

        private void LoadData()
        {
            string strQuery = "select a.*,b.KindText from tableTest a left join tableKind b on a.KindCode=b.KindCode ";
            string strShow = "ID,Subject,KindCode,KindText";     
            
            DataTable dt = m_Pager.ExecutePager(pageIndex, pageSize, strShow, strQuery, "", "ID desc", out pageCount, out recordCount);
            GridView1.DataSource = dt;
            GridView1.DataBind();
            Label1.Text = string.Format("共{0}条记录,每页{1}条,页次{2}/{3}",recordCount,pageSize,pageIndex,pageCount);
        }
        
       
        protected void btnJump_Click(object sender, EventArgs e)
        {
            int.TryParse(txtPageSize.Text, out pageIndex);
            LoadData();
        }
    }

     

     

    源 http://www.cnblogs.com/niuniu502/archive/2007/03/04/663175.html

    参考 http://www.cnblogs.com/KenBlove/articles/463340.html

    参考 http://blog.csdn.net/zhangyue0503/article/details/4603620

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  • 原文地址:https://www.cnblogs.com/jinmingjie/p/2632072.html
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