DateList翻页

来源：互联网发布：自学设计软件服装编辑：程序博客网时间：2024/04/30 09:02

前台代码：
－－－－－－
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="test.aspx.cs" Inherits="News_test" %>

<!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>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <TABLE id="Table1" style="Z-INDEX: 101; LEFT: 32px; WIDTH: 752px; POSITION: absolute; TOP: 16px; HEIGHT: 312px" cellSpacing="0" cellPadding="0" width="752" border="0">
            <TR>
                <TD style="HEIGHT: 29px"><FONT face="宋体">DataList分页技术和超级链接</FONT></TD>
            </TR>
            <TR>
                <TD style="HEIGHT: 252px">
                <asp:datalist id="DataList1" runat="server" Width="576px" Height="96px">
                     <HeaderTemplate>
                            定单编号<td>
                            员工编号<td>
                            定单日期<td>
                            运费<td>
                            运往所在城市
                     </HeaderTemplate>

            <asp:linkbutton id="FirstLB" runat="server" OnCommand="LinkButton_Click" CommandName="first">第一页</asp:linkbutton> 
            <asp:linkbutton id="PreviousLB" runat="server" OnCommand="LinkButton_Click" CommandName="prev">上一页</asp:linkbutton> 
            <asp:linkbutton id="NextLB" runat="server" OnCommand=LinkButton_Click CommandName="next">下一页</asp:linkbutton> 
            <asp:linkbutton id="EndLB" runat="server" OnCommand=LinkButton_Click CommandName="end">最后一页</asp:linkbutton>  
            总<asp:label id="TotalLbl" runat="server"></asp:label>页当前第<asp:label id="CurrentLbl" runat="server"></asp:label>页
            <asp:linkbutton id="JumpLB" runat="server" OnCommand=LinkButton_Click CommandName="jump">跳到</asp:linkbutton>第
            <asp:textbox id="TextBox1" runat="server" Width="90px"></asp:textbox>
            页</FONT></TD>
            </TR>
            </TABLE>
    </div>
    </form>
</body>
</html>
-------------------------------------------------
后台代码：
－－－－－－－－－－
using System;
using System.Data;
using System.Configuration;
using System.Collections;
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.Data.SqlClient;

public partial class News_test : System.Web.UI.Page
{
    int CurrentPage;//当前页数
    int PageSize;   //每页条数
    int PageCount; //总页数
    int RecordCount;//总条数
    private void Page_Load(object sender, System.EventArgs e)
    {
        // 在此处放置用户代码以初始化页面

PageSize = 10;//每页10条记录

        if (!Page.IsPostBack)
        {
             CurrentPage = 0;//当前页习惯设为0
            ViewState["PageIndex"] = 0;//页索引也设为0

//计算总共有多少记录
RecordCount = CalculateRecord();

            //计算总共有多少页
            if (RecordCount % PageSize == 0)
            {
                PageCount = RecordCount / PageSize;
            }
            else
            {
                PageCount = RecordCount / PageSize + 1;
            }

this.TotalLbl.Text = PageCount.ToString();//显示总页数
ViewState["PageCount"] = PageCount;//会话session 对整个 application 有效，而视图状态 viewstate相当于某个页面的 session

            this.DataListBind();//不可以放在初始化条件之前就绑定，那样的话，如果仅有一页的数据，“下一页”页仍然显示

        }

}

    //计算总共有多少条记录
    private int CalculateRecord()
    {
        try
        {
            int recordCount;
            SqlConnection con = new SqlConnection("server=127.0.0.1;database=Northwind;uid=sa;pwd=sa");//数据库使用Northwind;
            con.Open();

            string sql = "select count(*) as count from Orders";
            SqlCommand cmd = new SqlCommand(sql, con);
            SqlDataReader sdr = cmd.ExecuteReader();

            if (sdr.Read())
            {
                recordCount = Int32.Parse(sdr["count"].ToString());
            }

            else
            {
                recordCount = 0;
            }

            sdr.Close();
            con.Close();
            return recordCount;
        }

        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
    }

    //将数据绑定到Datalist控件
    public void DataListBind()
    {
        try
        {
            int StartIndex = CurrentPage * PageSize;//设定导入的起终地址
            string sql = "select * from Orders";
            DataSet ds = new DataSet();
            SqlConnection con = new SqlConnection("server=127.0.0.1;database=Northwind;uid=sa;pwd=sa");
            con.Open();

            SqlDataAdapter sda = new SqlDataAdapter(sql, con);
            sda.Fill(ds, StartIndex, PageSize, "orders");//这是sda.Fill方法的第一次重载，里面的变量分别是数据集DataSet ,开始记录数StartRecord，最大的记录数MaxRecord，数据表名TableName
            this.DataList1.DataSource = ds.Tables["orders"].DefaultView;
            this.DataList1.DataBind();
            this.PreviousLB.Enabled = true;
            this.NextLB.Enabled = true;
            if (CurrentPage == (PageCount - 1)) this.NextLB.Enabled = false;//当为最后一页时，下一页链接按钮不可用
            if (CurrentPage == 0) this.PreviousLB.Enabled = false;//当为第一页时，上一页按钮不可用
            this.CurrentLbl.Text = (CurrentPage + 1).ToString();//当前页数

}

        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
    }

    public void LinkButton_Click(Object sender, CommandEventArgs e)//自己编写的按钮点击事件
    {
        CurrentPage = (int)ViewState["PageIndex"];//获得当前页索引
        PageCount = (int)ViewState["PageCount"];//获得总页数

string cmd = e.CommandName;

//判断cmd，以判定翻页方向

        switch (cmd)
        {
            case "prev"://上一页
                if (CurrentPage > 0) CurrentPage--;
                break;

            case "next":
                if (CurrentPage < (PageCount - 1)) CurrentPage++;//下一页
                break;

            case "first"://第一页
                CurrentPage = 0;
                break;

            case "end"://最后一页
                CurrentPage = PageCount - 1;
                break;

            case "jump"://跳转到第几页
                if (this.TextBox1.Text.Trim() == "" || Int32.Parse(this.TextBox1.Text.Trim()) > PageCount)//如果输入数字为空或超出范围则返回
                {
                    return;
                }
                else
                {
                    CurrentPage = Int32.Parse(this.TextBox1.Text.ToString()) - 1;
                    break;
                }
        }
        ViewState["PageIndex"] = CurrentPage;//获得当前页

this.DataListBind();//重新将DataList绑定到数据库

}