[ASP.net WebForm] 使用PagedDataSource物件實現手寫分頁 (適合初學者)

2011-11-28

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ASP.net WebForm
2011-11-28

利用PagedDataSource物件來做分頁其實效率不好

因為它是把全部的資料抓下來後再進行分頁，但還是紀錄一下如何使用

畢竟初入門手寫分頁，我就是從PagedDataSource開始學起，比較簡單，即使不太會SQL語法的人都能輕易上手

先在本機DB建立測試資料


Create database pageDataBase
Go
use pageDataBase
Go
Create table tb_data
(
 id int identity primary key,
 title varchar(50)

)
Go

Insert into tb_data values ('A'),('B'),('C'),('D'),('E'),('F'),('G'),('H'),('I'),('J'),('K'),('L')
Go
Select * from pageDataBase.dbo.tb_data
/*總共12筆資料*/

新增一個WebSite專案

再對著專案，新增一個名為「PagedDataSourceDemo」的WebForm

接著在Web.config檔配置要Reuse的連線字串

環境都配置完成了

接著在PagedDataSourceDemo.aspx的設計頁面

拉出ListView(GridView也可以)

並擺上自己的分頁區塊


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

<!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></title>
    <style type="text/css">
        /*分頁區塊的CSS*/
        .rsmenu
        {
            color: #4c4c4c;
            padding: 15px 0;
            clear: both;
            text-align: center;
        }
        .rsmenu span, .rsmenu span a
        {
            color: #808e02;
        }
        .pgbtn
        {
            background: #808E02;
            border: none medium;
            color: #fff;
            cursor: pointer;
            width: 40px;
            height: 19px;
        }
        .pgbtn:hover
        {
            background: #99a535;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <%--表格式ListView--%>
    <asp:ListView ID="lv_showData" runat="server">
        <ItemTemplate>
            <tr>
                <td>
                    <asp:Literal ID="idLiteral" runat="server" Text='<%# Eval("id") %>' />
                </td>
                <td>
                    <asp:Literal ID="titleLiteral" runat="server" Text='<%# Eval("title") %>' />
                </td>
            </tr>
        </ItemTemplate>
        <LayoutTemplate>
            <table id="itemPlaceholderContainer" runat="server" align="center" cellpadding="0"
                cellspacing="0" border="1" style="border-style: solid;">
                <tr>
                    <th runat="server">
                        id
                    </th>
                    <th runat="server">
                        title
                    </th>
                </tr>
                <tr id="itemPlaceholder" runat="server">
                </tr>
            </table>
        </LayoutTemplate>
    </asp:ListView>
    <%--分頁區塊--%>
    <div class="rsmenu">
        合計<asp:Literal ID="li_totalRows" runat="server" />
        <span>｜
            <asp:LinkButton Text="最前頁" ID="lnkFirstPage" runat="server" OnClick="lnkFirstPage_Click" />
            ｜
            <asp:LinkButton Text="上一頁" ID="lnkPrePage" runat="server" OnClick="lnkPrePage_Click" />｜
        </span>選擇頁數&nbsp;&nbsp; <b>第<asp:DropDownList runat="server" ID="dl_currentPage">
        </asp:DropDownList>
            頁</b> <span>｜
                <asp:LinkButton Text="下一頁" ID="lnkNextPage" runat="server" OnClick="lnkNextPage_Click" />｜
                <asp:LinkButton Text="最後頁" runat="server" ID="lnkLastPage" OnClick="lnkLastPage_Click" />｜
            </span>每頁
        <asp:DropDownList runat="server" ID="dl_pageSize">
            <asp:ListItem Value="5" Text="5" />
            <asp:ListItem Value="10" Text="10" />
        </asp:DropDownList>
        筆
        <asp:Button ID="btnToPage" runat="server" CssClass="pgbtn" Text="跳頁" OnClick="btnToPage_Click" />
    </div>
    </form>
</body>
</html>

然後把Code-Behind的事件也都補起來


    //第一頁Click
    protected void lnkFirstPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = "1";//到第一頁
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //上一頁Click
    protected void lnkPrePage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) - 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }
    //下一頁Click
    protected void lnkNextPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) + 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //最後一頁
    protected void lnkLastPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = dl_currentPage.Items[dl_currentPage.Items.Count - 1].Value;
        this.btnToPage_Click(null, null);//跳頁事件
    }

    #region 跳頁事件postback的處理
    protected void btnToPage_Click(object sender, EventArgs e)
    {
        #region 防呆，當查詢無資料時，dl_currentPage.SelectedValue會空字串，為了避免再按一次搜尋或再次postback時，程式掛掉，加入以下判斷
        int currentPage = 1;
        if (dl_currentPage.SelectedValue == "")
        {
            currentPage = 1;
        }
        else
        {
            currentPage = Convert.ToInt32(dl_currentPage.SelectedValue);
        }
        
        #endregion
    }
    #endregion

然後到設計畫面按Ctrl+Shift+W，如果執行成功的話，表示事件都補齊了

接下來要新增一個類別，命名DBUtility.cs

因為是Web Site專案，所以類別會被放到App_Code資料夾下

接著補上以下的Code


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
/*要引用此兩個命名空間*/
using System.Web.UI.WebControls;
using System.Data;

/// <summary>
/// DBUtility 的摘要描述
/// </summary>
public class DBUtility
{
	public DBUtility()
	{
		//
		// TODO: 在此加入建構函式的程式碼
		//
	}

     

    #region 分頁資料繫結控制項，例如：ListView、GridView
    /// <summary>
    /// 分頁資料繫結控制項，例如：ListView、GridView，畫面上有用到Container.DataItemIndex的話，有可能出錯
    /// </summary>
    /// <param name="ds">要分頁的DataSet</param>
    /// <param name="pageSize">每頁顯示幾筆</param>
    /// <param name="currentPage">目前第幾頁</param>
    /// <param name="PageControl">要分頁的控制項，例如：ListView、GridView</param>
    /// <returns>回傳PagedDataSource</returns>
    public static PagedDataSource pageData(DataSet ds, int pageSize, int currentPage, DataBoundControl PageControl)
    {

        PagedDataSource objPageData = new PagedDataSource();
        //此為必填屬性
        objPageData.AllowPaging = true;

        //指定要分頁的資料來源
        objPageData.DataSource = ds.Tables[0].DefaultView;

        objPageData.PageSize = pageSize;

        objPageData.CurrentPageIndex = currentPage - 1;


        PageControl.DataSource = objPageData;
        PageControl.DataBind();

        return objPageData;
    }

    #endregion
}

接下來先簡單地在Page_Load寫個撈資料的語法


    //連線字串
    string connStr = WebConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            DataSet ds = new DataSet();
            using (SqlConnection conn = new SqlConnection(this.connStr))
            {
                SqlDataAdapter da = new SqlDataAdapter("Select * from tb_data Order by id ASC", conn);
                
                da.Fill(ds);
            }

            int pageSize = 5;//每頁顯示5筆
            int currentPage = 1;//目前在第1頁
            //叫用DBUtilty來分頁
            DBUtility.pageData(ds,pageSize,currentPage,  lv_showData);
            
        }
    }

執行結果：

接下來要把底下的合計總筆數顯示出來，且(目前)第幾頁的下拉選單資料也要填一填，不然按下上一頁、下一頁按鈕後，程式會掛掉


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using System.Web.Configuration;

public partial class PagedDataSourceDemo : System.Web.UI.Page
{
    //連線字串
    string connStr = WebConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
   string sqlSelect = " Select * from tb_data Where 1=1 ";
    string sqlOrderBy = " Order by id ASC";
    /*修改Page_Load事件的Code*/
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)//Get Method要做的動作
        {
            //預設
            int pageSize = 5;//每頁顯示5筆
            int currentPage = 1;//目前在第1頁
            this.showData(currentPage, pageSize, this.sqlSelect + this.sqlOrderBy);
            
        }
    }

    


    /*追加showData方法*/
    #region 分頁資料，總筆數、總頁數文字顯示處理
    protected void showData(int currentPage, int pageSize, string sql)
    {

        DataSet ds = this.Query(sql);//查詢出此次的資料
       

        #region 總頁數、總筆數文字顯示處理

        int totalRows = ds.Tables[0].Rows.Count;//總筆數
        li_totalRows.Text = totalRows.ToString();

        //ListView顯示分頁後的資料，並做DataBind()
        System.Web.UI.WebControls.PagedDataSource pds =
                                                  DBUtility.pageData(ds, pageSize, currentPage, lv_showData);
        //總頁數
        //int totalPages = (totalRows / pageSize);//取商數
        //if (totalRows % pageSize > 0)
        //{
        //    totalPages++;
        //}
        int totalPages = pds.PageCount;
        
        //防呆寫法
        if (currentPage > totalPages)
            currentPage = totalPages;
        if (currentPage < 1)
            currentPage = 1;



        dl_currentPage.Items.Clear();
        for (int i = 1; i <= totalPages; i++)
        {
            dl_currentPage.Items.Add(i.ToString());
        }
        //目前第幾頁的下拉選單選擇值
        dl_currentPage.SelectedValue = currentPage.ToString();
        //每頁顯示幾筆的下拉選單選擇值
        dl_pageSize.SelectedValue = pageSize.ToString();

        //第一頁和最後一頁時，第一頁、上一頁、下一頁、最末頁按鈕Enabled的處理防呆
        if (currentPage == 1)//目前在第一頁
        {
            lnkFirstPage.Enabled = false;
            lnkPrePage.Enabled = false;
        }
        else
        {
            lnkFirstPage.Enabled = true;
            lnkPrePage.Enabled = true;
        }
        if (currentPage == totalPages)//目前在最後一頁
        {
            lnkLastPage.Enabled = false;
            lnkNextPage.Enabled = false;
        }
        else
        {
            lnkLastPage.Enabled = true;
            lnkNextPage.Enabled = true;
        }

        #endregion



        
       
        




    }
    #endregion

    /*追加Query 方法*/
    /// <summary>
    /// 傳入SQL查詢語句，回傳DataSet
    /// </summary>
    /// <param name="sql"></param>
    /// <returns></returns>
    private DataSet Query(string sql)
    {
        DataSet ds = new DataSet();
        using (SqlConnection conn = new SqlConnection(this.connStr))
        {
            SqlDataAdapter da = new SqlDataAdapter(sql,conn);
            da.Fill(ds);
        }
        return ds;
    
    
    }






    //第一頁Click
    protected void lnkFirstPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = "1";//到第一頁
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //上一頁Click
    protected void lnkPrePage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) - 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }
    //下一頁Click
    protected void lnkNextPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) + 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //最後一頁
    protected void lnkLastPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = dl_currentPage.Items[dl_currentPage.Items.Count - 1].Value;
        this.btnToPage_Click(null, null);//跳頁事件
    }

   /*修改btnToPage_Click事件的Code*/
    #region 跳頁事件postback的處理
    protected void btnToPage_Click(object sender, EventArgs e)
    {
        #region 防呆，當查詢無資料時，dl_currentPage.SelectedValue會空字串，為了避免再按一次搜尋或再次postback時，程式掛掉，加入以下判斷
        int currentPage = 1;
        if (dl_currentPage.SelectedValue == "")
        {
            currentPage = 1;
        }
        else
        {
            currentPage = Convert.ToInt32(dl_currentPage.SelectedValue);
        }
        /*追加此行*/
        this.showData(currentPage, Convert.ToInt32(dl_pageSize.SelectedValue), this.sqlSelect + this.sqlOrderBy);
        #endregion
    }
    #endregion
}

再執行一次網頁

第一次執行正常

跳到第2頁也正常

跳到第3頁也正常

接下來就有問題了

若是選擇每頁顯示10筆，到第3頁，因為總筆數才12筆不足30筆，程式會掛掉

所以總頁數的部份在showData方法要做個防呆


#region 分頁資料，總筆數、總頁數文字顯示處理
    protected void showData(int currentPage, int pageSize, string sql)
    {

        DataSet ds = this.Query(sql);//查詢出此次的資料
       

        #region 總頁數、總筆數文字顯示處理

        int totalRows = ds.Tables[0].Rows.Count;//總筆數
        li_totalRows.Text = totalRows.ToString();

        //總頁數(自己算)
        int totalPages = (totalRows / pageSize);//取商數(總筆數除以每頁顯示幾筆，得到總頁數)
        if (totalRows % pageSize > 0)//若餘數大於0，不整除的話，總頁數要加1，道理如同小學數學題 多出來的學生也要多叫一部遊覽車送去郊遊是一樣的
        {
            totalPages++;
        }
        /*註解掉下面這行*/
        //int totalPages = pds.PageCount;

        //防呆寫法
        if (currentPage > totalPages)
            currentPage = totalPages;
        if (currentPage < 1)
            currentPage = 1;


        //ListView顯示分頁後的資料，並做DataBind()，這次的currentPage經過防呆後，應該是正確的值了
        System.Web.UI.WebControls.PagedDataSource pds =
                                                  DBUtility.pageData(ds, pageSize, currentPage, lv_showData);
        
        
        



        dl_currentPage.Items.Clear();
        for (int i = 1; i <= totalPages; i++)
        {
            dl_currentPage.Items.Add(i.ToString());
        }
        //目前第幾頁的下拉選單選擇值
        dl_currentPage.SelectedValue = currentPage.ToString();
        //每頁顯示幾筆的下拉選單選擇值
        dl_pageSize.SelectedValue = pageSize.ToString();

        //第一頁和最後一頁時，第一頁、上一頁、下一頁、最末頁按鈕Enabled的處理防呆
        if (currentPage == 1)//目前在第一頁
        {
            lnkFirstPage.Enabled = false;
            lnkPrePage.Enabled = false;
        }
        else
        {
            lnkFirstPage.Enabled = true;
            lnkPrePage.Enabled = true;
        }
        if (currentPage == totalPages)//目前在最後一頁
        {
            lnkLastPage.Enabled = false;
            lnkNextPage.Enabled = false;
        }
        else
        {
            lnkLastPage.Enabled = true;
            lnkNextPage.Enabled = true;
        }

        #endregion



        
       
        




    }
    #endregion

這次從每頁顯示10筆，到第3頁，按下跳頁按鈕後

會自動變成每頁顯示10筆的最後一頁(第2頁)

分頁功能雖然至此完成，但還需要再完善

這次在畫面上拉一個下拉選單


<%--查詢條件的下拉選單--%>
    <asp:DropDownList runat="server" ID="ddl_SelectID" AutoPostBack="true" 
        onselectedindexchanged="btnToPage_Click">
        <asp:ListItem Text="請選擇" Value="-1" />
        <asp:ListItem Text="5" Value="5" />
        <asp:ListItem Text="10" Value="10" />
    </asp:DropDownList>

Code-Behind也要新增一個queryData方法，並修改btnToPage_Click事件


//跳頁postback或假設按了搜尋按鈕都要經過此SQL語法
    protected void queryData(int currentPage, int pageSize)
    {
        string sql = this.sqlSelect;

        if (ddl_SelectID.SelectedIndex>0)//有選擇
        {
            sql += " And id > '"+ddl_SelectID.SelectedValue+"'";
        }

        //排序
        sql += this.sqlOrderBy;

        this.showData(currentPage, pageSize, sql);


    }


#region 跳頁事件postback的處理
    protected void btnToPage_Click(object sender, EventArgs e)
    {
        #region 防呆，當查詢無資料時，dl_currentPage.SelectedValue會空字串，為了避免再按一次搜尋或再次postback時，程式掛掉，加入以下判斷
        int currentPage = 1;
        if (dl_currentPage.SelectedValue == "")
        {
            currentPage = 1;
        }
        else
        {
            currentPage = Convert.ToInt32(dl_currentPage.SelectedValue);
        }

        /*每次跳頁postback就要經過queryData方法*/
        this.queryData(currentPage, Convert.ToInt32(dl_pageSize.SelectedValue));
        #endregion
    }
    #endregion

全部完整的Code

.aspx


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

<!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></title>
    <style type="text/css">
        /*分頁區塊的CSS*/
        .rsmenu
        {
            color: #4c4c4c;
            padding: 15px 0;
            clear: both;
            text-align: center;
        }
        .rsmenu span, .rsmenu span a
        {
            color: #808e02;
        }
        .pgbtn
        {
            background: #808E02;
            border: none medium;
            color: #fff;
            cursor: pointer;
            width: 40px;
            height: 19px;
        }
        .pgbtn:hover
        {
            background: #99a535;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <%--查詢條件的下拉選單--%>
    <asp:DropDownList runat="server" ID="ddl_SelectID" AutoPostBack="true" 
        onselectedindexchanged="btnToPage_Click">
        <asp:ListItem Text="請選擇" Value="-1" />
        <asp:ListItem Text="5" Value="5" />
        <asp:ListItem Text="10" Value="10" />
    </asp:DropDownList>
    <%--表格式ListView--%>
    <asp:ListView ID="lv_showData" runat="server">
        <ItemTemplate>
            <tr>
                <td>
                    <asp:Literal ID="idLiteral" runat="server" Text='<%# Eval("id") %>'  />
                </td>
                <td>
                    <asp:Literal ID="titleLiteral" runat="server" Text='<%# Eval("title") %>' />
                </td>
            </tr>
        </ItemTemplate>
        <LayoutTemplate>
            <table id="itemPlaceholderContainer" runat="server" align="center" cellpadding="0"
                cellspacing="0" border="1" style="border-style: solid;">
                <tr>
                    <th runat="server">
                        id
                    </th>
                    <th runat="server">
                        title
                    </th>
                </tr>
                <tr id="itemPlaceholder" runat="server">
                </tr>
            </table>
        </LayoutTemplate>
    </asp:ListView>
    <%--分頁區塊--%>
    
    <div class="rsmenu">
        合計<asp:Literal ID="li_totalRows" runat="server" />
        <span>｜
            <asp:LinkButton Text="最前頁" ID="lnkFirstPage" runat="server" OnClick="lnkFirstPage_Click" />
            ｜
            <asp:LinkButton Text="上一頁" ID="lnkPrePage" runat="server" OnClick="lnkPrePage_Click" />｜
        </span>選擇頁數&nbsp;&nbsp; <b>第<asp:DropDownList runat="server" ID="dl_currentPage">
        </asp:DropDownList>
            頁</b> <span>｜
                <asp:LinkButton Text="下一頁" ID="lnkNextPage" runat="server" OnClick="lnkNextPage_Click" />｜
                <asp:LinkButton Text="最後頁" runat="server" ID="lnkLastPage" OnClick="lnkLastPage_Click" />｜
            </span>每頁
        <asp:DropDownList runat="server" ID="dl_pageSize">
            <asp:ListItem Value="5" Text="5" />
            <asp:ListItem Value="10" Text="10" />
        </asp:DropDownList>
        筆
        <asp:Button ID="btnToPage" runat="server" CssClass="pgbtn" Text="跳頁" OnClick="btnToPage_Click" />
    </div>
    </form>
</body>
</html>


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using System.Web.Configuration;

public partial class PagedDataSourceDemo : System.Web.UI.Page
{
    //連線字串
    string connStr = WebConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
    string sqlSelect = " Select * from tb_data Where 1=1 ";
    string sqlOrderBy = " Order by id ASC";
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)//Get Method要做的動作
        {
            //預設
            int pageSize = 5;//每頁顯示5筆
            int currentPage = 1;//目前在第1頁
            this.showData(currentPage, pageSize, this.sqlSelect + this.sqlOrderBy);
            
        }
    }

    //跳頁postback或假設按了搜尋按鈕都要經過此SQL語法
    protected void queryData(int currentPage, int pageSize)
    {
        string sql = this.sqlSelect;

        if (ddl_SelectID.SelectedIndex>0)//有選擇
        {
            sql += " And id > '"+ddl_SelectID.SelectedValue+"'";
        }

        //排序
        sql += this.sqlOrderBy;

        this.showData(currentPage, pageSize, sql);


    }



    #region 分頁資料，總筆數、總頁數文字顯示處理
    protected void showData(int currentPage, int pageSize, string sql)
    {

        DataSet ds = this.Query(sql);//查詢出此次的資料
       

        #region 總頁數、總筆數文字顯示處理

        int totalRows = ds.Tables[0].Rows.Count;//總筆數
        li_totalRows.Text = totalRows.ToString();

        //總頁數(自己算)
        int totalPages = (totalRows / pageSize);//取商數(總筆數除以每頁顯示幾筆，得到總頁數)
        if (totalRows % pageSize > 0)//若餘數大於0，不整除的話，總頁數要加1，道理如同小學數學題 多出來的學生也要多叫一部遊覽車送去郊遊是一樣的
        {
            totalPages++;
        }
        /*註解掉下面這行*/
        //int totalPages = pds.PageCount;

        //防呆寫法
        if (currentPage > totalPages)
            currentPage = totalPages;
        if (currentPage < 1)
            currentPage = 1;


        //ListView顯示分頁後的資料，並做DataBind()，這次的currentPage經過防呆後，應該是正確的值了
        System.Web.UI.WebControls.PagedDataSource pds =
                                                  DBUtility.pageData(ds, pageSize, currentPage, lv_showData);
        
        
        



        dl_currentPage.Items.Clear();
        for (int i = 1; i <= totalPages; i++)
        {
            dl_currentPage.Items.Add(i.ToString());
        }
        //目前第幾頁的下拉選單選擇值
        dl_currentPage.SelectedValue = currentPage.ToString();
        //每頁顯示幾筆的下拉選單選擇值
        dl_pageSize.SelectedValue = pageSize.ToString();

        //第一頁和最後一頁時，第一頁、上一頁、下一頁、最末頁按鈕Enabled的處理防呆
        if (currentPage == 1)//目前在第一頁
        {
            lnkFirstPage.Enabled = false;
            lnkPrePage.Enabled = false;
        }
        else
        {
            lnkFirstPage.Enabled = true;
            lnkPrePage.Enabled = true;
        }
        if (currentPage == totalPages)//目前在最後一頁
        {
            lnkLastPage.Enabled = false;
            lnkNextPage.Enabled = false;
        }
        else
        {
            lnkLastPage.Enabled = true;
            lnkNextPage.Enabled = true;
        }

        #endregion



        
       
        




    }
    #endregion

    /// <summary>
    /// 傳入SQL查詢語句，回傳DataSet
    /// </summary>
    /// <param name="sql"></param>
    /// <returns></returns>
    private DataSet Query(string sql)
    {
        DataSet ds = new DataSet();
        using (SqlConnection conn = new SqlConnection(this.connStr))
        {
            SqlDataAdapter da = new SqlDataAdapter(sql,conn);
            da.Fill(ds);
        }
        return ds;
    
    
    }






    //第一頁Click
    protected void lnkFirstPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = "1";//到第一頁
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //上一頁Click
    protected void lnkPrePage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) - 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }
    //下一頁Click
    protected void lnkNextPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = Convert.ToInt32(dl_currentPage.SelectedValue) + 1 + "";
        this.btnToPage_Click(null, null);//跳頁事件
    }

    //最後一頁
    protected void lnkLastPage_Click(object sender, EventArgs e)
    {
        dl_currentPage.SelectedValue = dl_currentPage.Items[dl_currentPage.Items.Count - 1].Value;
        this.btnToPage_Click(null, null);//跳頁事件
    }

    #region 跳頁事件postback的處理
    protected void btnToPage_Click(object sender, EventArgs e)
    {
        #region 防呆，當查詢無資料時，dl_currentPage.SelectedValue會空字串，為了避免再按一次搜尋或再次postback時，程式掛掉，加入以下判斷
        int currentPage = 1;
        if (dl_currentPage.SelectedValue == "")
        {
            currentPage = 1;
        }
        else
        {
            currentPage = Convert.ToInt32(dl_currentPage.SelectedValue);
        }

        /*每次跳頁postback就要經過queryData方法*/
        this.queryData(currentPage, Convert.ToInt32(dl_pageSize.SelectedValue));
        #endregion
    }
    #endregion
  
}

執行測試查詢條件：

預設畫面

下拉選單選5 (id大於5的條件)

第2頁

拉回「請選擇」(SQL撈全部的資料，目前在第2頁，每頁顯示5筆)

完整研究包

建議下一篇閱讀：

[ASP.net WebForm] 製作可重複使用的分頁WebUserControl

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