ASP.NET技巧：access下的分頁方案

2024-07-10 13:13:40

字體：大中小

來源：轉載

供稿：網友

具體不多說了，只貼出相關源碼~

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

/**//// <summary>
/// 名稱：access下的分頁方案（仿sql存儲過程）
/// 作者：cncxz(蟲蟲)
/// 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>
/// 打開連接
/// </summary>
public void ConnOpen()
{
if (m_Conn.State != ConnectionState.Open)
m_Conn.Open();
}
/**//// <summary>
/// 關閉連接
/// </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>
/// 獲取當前頁應該顯示的記錄，注意：查詢中必須包含名為ID的自動編號列，若不符合你的要求，就修改一下源碼吧 :)
/// </summary>
/// <param name="pageIndex">當前頁碼</param>
/// <param name="pageSize">分頁容量</param>
/// <param name="showString">顯示的字段</param>
/// <param name="queryString">查詢字符串，支持聯合查詢</param>
/// <param name="whereString">查詢條件，若有條件限制則必須以where 開頭</param>
/// <param name="orderString">排序規則</param>
/// <param name="pageCount">傳出參數：總頁數統計</param>
/// <param name="recordCount">傳出參數：總記錄統計</param>
/// <returns>裝載記錄的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)//第一頁
{
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)//超出總頁數
{
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;
}
}

還有調用示例：html代碼

<%@ 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">

示例的codebehind代碼

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}條記錄，每頁{1}條，頁次{2}/{3}",recordCount,pageSize,pageIndex,pageCount);
}

protected void btnJump_Click(object sender, EventArgs e)
{
int.TryParse(txtPageSize.Text, out pageIndex);
LoadData();
}
}