为DataGrid的自带分页添加首页、尾页及状态功能

来源:岁月联盟 编辑:zhu 时间:2004-10-14
DataGrid提供了分页功能,不过看上去功能有限,但是我们可以通过DataGrid的一些属性来获取状态以及增加首页、尾页功能按钮。这里没有使用DataGrid的自定义分页功能,如果在速度效率不是很讲究的情况下,由DataGrid自己管理分页还是不错的,付出的代价就是要把整个相关数据取出来后再删选指定页的数据。好处就是开发速度快,不需要写分页的存储过程。本文事例使用的是Sql Server中的Northwind数据库。运行界面如下:



对于前台的显示界面,我放了一个DataGrid;四个LinkButton导向按钮;四个Literal来显示纪录状态。

剩下的就是用表格定位。

这里需要设置DataGrid的AllowPaging属性为True,同时设置AllowCustomPaging属性位false(默认为false),设置PagerStyle的Visible属性为False,使前台不显示。

前台的代码如下:

<%@ Page language="c#" Codebehind="DataGridPaging.aspx.cs" AutoEventWireup="false" Inherits="ZZ.AspnetPaging.DataGridPaging" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >

<HTML>

<HEAD>

<title>DataGridPaging</title>

<meta content="Microsoft Visual Studio .NET 7.1" name="GENERATOR">

<meta content="C#" name="CODE_LANGUAGE">

<meta content="JavaScript" name="vs_defaultClientScript">

<meta content="http://schemas.microsoft.com/intellisense/ie5" name="vs_targetSchema">

</HEAD>

<body>

<form id="Form1" method="post" runat="server">

<TABLE id="Table1" style="FONT-SIZE: 9pt" cellSpacing="1" cellPadding="1" width="450" align="center"

border="1">

<TR>

<TD><asp:datagrid id="DataGrid1" runat="server" PageSize="5" Width="100%" AllowPaging="True">

<HeaderStyle Font-Size="9pt"></HeaderStyle>

<FooterStyle Font-Size="9pt"></FooterStyle>

<PagerStyle Visible="False" Font-Size="9pt" Mode="NumericPages"></PagerStyle>

</asp:datagrid></TD>

</TR>

</TABLE>

<TABLE id="Table2" style="FONT-SIZE: 9pt" cellSpacing="1" cellPadding="1" width="450" align="center"

border="1">

<TR>

<TD style="WIDTH: 207px">

<asp:linkbutton id="LBtnFirst" runat="server" CommandName="First">首页</asp:linkbutton>

<asp:linkbutton id="LBtnPrev" runat="server" CommandName="Prev">上一页</asp:linkbutton>

<asp:linkbutton id="LBtnNext" runat="server" CommandName="Next">下一页</asp:linkbutton>

<asp:linkbutton id="LBtnLast" runat="server" CommandName="Last">尾页</asp:linkbutton> </TD>

<TD>第

<asp:literal id="LtlPageIndex" runat="server"></asp:literal>页 共

<asp:literal id="LtlPageCount" runat="server"></asp:literal>页 每页

<asp:literal id="LtlPageSize" runat="server"></asp:literal>条 共

<asp:literal id="LtlRecordCount" runat="server"></asp:literal>条

</TD>

</TR>

</TABLE>

</form>

</body>

</HTML>

后台cs文件代码,DataGridPaging类从System.Web.UI.Page继承,在数据绑定时需要注意没有数据的情况(0页时),以及当页数减少时避免前台正在反页导致缺页。

using System;

using System.Collections;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Web;

using System.Web.SessionState;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.HtmlControls;

using System.Data.SqlClient;

using System.Configuration;



namespace ZZ.AspnetPaging

{

public class DataGridPaging : System.Web.UI.Page

{

private static string connString = ConfigurationSettings.AppSettings["ConnString"];

private int recordCount;

private int pageCount;



protected System.Web.UI.WebControls.LinkButton LBtnFirst;

protected System.Web.UI.WebControls.LinkButton LBtnPrev;

protected System.Web.UI.WebControls.LinkButton LBtnNext;

protected System.Web.UI.WebControls.LinkButton LBtnLast;

protected System.Web.UI.WebControls.Literal LtlPageIndex;

protected System.Web.UI.WebControls.Literal LtlPageCount;

protected System.Web.UI.WebControls.Literal LtlPageSize;

protected System.Web.UI.WebControls.Literal LtlRecordCount;

protected System.Web.UI.WebControls.DataGrid DataGrid1;



private void Page_Load(object sender, System.EventArgs e)

{

if(!Page.IsPostBack)

{

DataGridDataBind();

}

}



//绑定数据

private void DataGridDataBind()

{

DataSet ds = GetCustomersData();

recordCount = ds.Tables[0].Rows.Count;

//获取当前的页数

pageCount = (int)Math.Ceiling( recordCount * 1.0 / PageSize);

//避免纪录从有到无时,并且已经进行过反页的情况下CurrentPageIndex > PageCount出错

if(recordCount ==0)

{

this.DataGrid1.CurrentPageIndex = 0;

}

else if(this.DataGrid1.CurrentPageIndex >= pageCount)

{

this.DataGrid1.CurrentPageIndex = pageCount - 1;

}

this.DataGrid1.DataSource = ds;

this.DataGrid1.DataBind();

NavigationStateChange();

}



#region Web 窗体设计器生成的代码

override protected void OnInit(EventArgs e)

{

//

// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。

//

InitializeComponent();

base.OnInit(e);

}



/// <summary>

/// 设计器支持所需的方法 - 不要使用代码编辑器修改

/// 此方法的内容。

/// </summary>

private void InitializeComponent()

{

this.LBtnFirst.Click += new System.EventHandler(this.LBtnNavigation_Click);

this.LBtnPrev.Click += new System.EventHandler(this.LBtnNavigation_Click);

this.LBtnNext.Click += new System.EventHandler(this.LBtnNavigation_Click);

this.LBtnLast.Click += new System.EventHandler(this.LBtnNavigation_Click);

this.Load += new System.EventHandler(this.Page_Load);



}

#endregion



private void LBtnNavigation_Click(object sender, System.EventArgs e)

{

LinkButton btn = (LinkButton)sender;

switch(btn.CommandName)

{

case "First":

PageIndex = 0;

break;

case "Prev"://if( PageIndex > 0 )

PageIndex = PageIndex - 1;

break;

case "Next"://if( PageIndex < PageCount -1)

PageIndex = PageIndex + 1;

break;

case "Last":

PageIndex = PageCount - 1;

break;

}

DataGridDataBind();

}

//数据绑定

public static DataSet GetCustomersData()

{

SqlConnection conn = new SqlConnection(connString);

string sqlStr = "SELECT CustomerID, CompanyName,Address,Phone FROM Customers";

SqlCommand comm = new SqlCommand( sqlStr ,conn);

SqlDataAdapter dataAdapter = new SqlDataAdapter(comm);

DataSet ds = new DataSet();

dataAdapter.Fill(ds);

return ds;

}



/// <summary>

/// 控制导航按钮或数字的状态

/// </summary>

public void NavigationStateChange()

{

if( PageCount <= 1 )//( RecordCount <= PageSize )//小于等于一页

{

this.LBtnFirst.Enabled = false;

this.LBtnPrev.Enabled = false;

this.LBtnNext.Enabled = false;

this.LBtnLast.Enabled = false;

}

else //有多页

{

if( PageIndex == 0 )//当前为第一页

{

this.LBtnFirst.Enabled = false;

this.LBtnPrev.Enabled = false;

this.LBtnNext.Enabled = true;

this.LBtnLast.Enabled = true;



}

else if( PageIndex == PageCount - 1 )//当前为最后页

{

this.LBtnFirst.Enabled = true;

this.LBtnPrev.Enabled = true;

this.LBtnNext.Enabled = false;

this.LBtnLast.Enabled = false;



}

else //中间页

{

this.LBtnFirst.Enabled = true;

this.LBtnPrev.Enabled = true;

this.LBtnNext.Enabled = true;

this.LBtnLast.Enabled = true;

}



}

if(RecordCount == 0)//当没有纪录时DataGrid.PageCount会显示1页

this.LtlPageCount.Text = "0";

else

this.LtlPageCount.Text = PageCount.ToString();

if(RecordCount == 0)

this.LtlPageIndex.Text = "0";

else

this.LtlPageIndex.Text = (PageIndex + 1).ToString();//在有页数的情况下前台显示页数加1

this.LtlPageSize.Text = PageSize.ToString();

this.LtlRecordCount.Text = RecordCount.ToString();

}





// 总页数

public int PageCount

{

get{return this.DataGrid1.PageCount;}

}

//页大小

public int PageSize

{

get{return this.DataGrid1.PageSize;}

}

//页索引,从零开始

public int PageIndex

{

get{return this.DataGrid1.CurrentPageIndex;}

set{this.DataGrid1.CurrentPageIndex = value;}

}

// 纪录总数

public int RecordCount

{

get{return recordCount;}

set{recordCount = value;}

}

}

}