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本文讲述的是如何利用 XMLHttpRequest 来对 Repeater 控件进行无刷新分页。

实现的方式是,使用XMLHttpRequest对象异步向服务器发送post 请求,传递设置好的每页显示记录数,当前页码和记录总数。服务器端接收到请求时,根据参数从数据库中查询相应记录,并通过Repeater 控件将数据显示出来,然后调用Repeater 的RenderControl 方法 将Repeater 绑定后生成的HTML代码作为服务器端的响应文本返回给客户端,客户端接到响应后替换Repeater 的相应HTML代码,从而实现了Repeater 无刷新分页。

需要注意的地方:

1、显示首页记录时,首页和上一页不可用,同理,显示末页记录时,末页和下一页不可用。

2、重新设置每页显示记录数时,要保持当前的页码不变,分页数改变。

下面看代码实现:

首先,创建一个WEB窗体,命名为 RepeaterDemo.aspx

代码如下:

<%@ Page Language="C#" CodeFile="RepeaterDemo.aspx.cs" Inherits="RepeaterDemo" %>

<!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>
    <style>
    <!--   
    .n{TEXT-DECORATION:none;cursor:pointer} a{color:black} a:hover{color:blue}
    .m{TEXT-DECORATION:none;cursor:default} a{color:black}
    //-->
    </style>
    <script type="text/javascript">
        var xmlHttp=null;     
        var index,size="10";
        function $(id)
        {
            return document.getElementByIdx_x_x(id);
        }
        function createXMLHttpRequest()
        {
            if(xmlHttp == null){
                if(window.XMLHttpRequest) {
                    //Mozilla 浏览器
                    xmlHttp = new XMLHttpRequest();
                }else if(window.ActiveXObject) {
                    // IE浏览器
                    try {
                        xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
                    } catch (e) {
                        try {
                            xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
                        } catch (e) {
                            alert('创建失败');
                        }
                    }
                }
            }
        }
       
        function openAjax(para)
        
            if( xmlHttp == null)
                         
                createXMLHttpRequest(); 
                if( xmlHttp == null)
                {
                    alert('出错');
                    return ;
                }
                                                                  
           
            xmlHttp.open("post","RepeaterDemoResult.aspx?date="+new Date().getTime(),true);            
           
            xmlHttp.onreadystatechange=xmlHttpChange;  
           
            xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded");

            xmlHttp.send(para);          
        }
       
        function xmlHttpChange()
                          
            if(xmlHttp.readyState==4)
                      
                if(xmlHttp.status==200)
                                  
                    $('resultDiv').innerHTML=xmlHttp.responseText;                    
                    $('<%=lblCurrentPage.ClientID %>').innerText=index==null?$('<%=lblCurrentPage.ClientID %>').innerText:index;
                    if(index==1)
                    {
                        $('<%=lbtnFirst.ClientID %>').disabled=true;
                        $('<%=lbtnPrevious.ClientID %>').disabled=true;    
                        $('<%=lbtnFirst.ClientID %>').className='m';
                        $('<%=lbtnPrevious.ClientID %>').className='m';                                   
                    }
                    else
                    {
                        $('<%=lbtnFirst.ClientID %>').disabled='';
                        $('<%=lbtnPrevious.ClientID %>').disabled='';
                        $('<%=lbtnFirst.ClientID %>').className='n';
                        $('<%=lbtnPrevious.ClientID %>').className='n';     
                    }
                    if(index==document.getElementByIdx_x_x('<%=lblPageCount.ClientID %>').innerText)
                    {
                        $('<%=lbtnNext.ClientID %>').disabled=true;
                        $('<%=lbtnLast.ClientID %>').disabled=true;
                        $('<%=lbtnNext.ClientID %>').className='m';
                        $('<%=lbtnLast.ClientID %>').className='m';
                    }
                    else
                    {
                        $('<%=lbtnNext.ClientID %>').disabled=false;
                        $('<%=lbtnLast.ClientID %>').disabled=false; 
                        $('<%=lbtnNext.ClientID %>').className='n';
                        $('<%=lbtnLast.ClientID %>').className='n';      
                    }
                }
            }
        }
        function getHTML(operate)
        {
            if(event.srcElement.disabled)
            {
                return;
            }
            var currentPage;
            var pageSize=$('<%=txtPageSize.ClientID %>').value;
            var count=$('<%=lblCount.ClientID %>').innerText;
            if(operate=='f')
            {
                currentPage=1;               
            }
            else if(operate=='p')
            {
                currentPage=parseInt($('<%=lblCurrentPage.ClientID %>').innerText)-1;             
            }
            else if(operate=='n')
            {
                currentPage=parseInt($('<%=lblCurrentPage.ClientID %>').innerText)+1;
            }
            else if(operate=='l')
            {
                currentPage=$('<%=lblPageCount.ClientID %>').innerText;
            }
            else if(operate=='c')
            {
                currentPage=$('<%=lblCurrentPage.ClientID %>').innerText;
                if(pageSize==size)
                {
                    return ;
                }
                size=pageSize;          
            }
            else
            {
                return ;
            
            index=currentPage;                   
            var para="pageNum="+currentPage+"&pageSize="+pageSize+"&count="+count;           
            openAjax(para);
        }
        function verify()
             
            if(isNaN(parseInt($('<%=txtPageSize.ClientID %>').value)))
            {
                alert('请输入数字!');
                return false;
                     
            getHTML('c');
            var count=parseInt($('<%=lblCount.ClientID %>').innerText);
            if(isNaN(count))
            {
                return;
            }
            var pageCount=(count%size==0)?count/size:(count-(count%size))/size+1;
            $('<%=lblPageCount.ClientID %>').innerText=pageCount; 
            var temp=parseInt($('<%=lblCurrentPage.ClientID %>').innerText);          
            if(pageCount<temp)
            {
                $('<%=lblCurrentPage.ClientID %>').innerText=pageCount;
                index=pageCount;
            }
        }
    </script>
</head>
<body>
    <form id="form1" runat="server">   
    <div id='resultDiv' style="cursor:auto">
        <asp:Repeater ID="rp" runat="server">
        <HeaderTemplate>
        <table><tr><td>编号</td><td>名称</td><td>价格</td><td>库存</td></tr>
        </HeaderTemplate>
        <AlternatingItemTemplate><tr><td><%#eval_r("ProductID") %></td><td><%#eval_r("ProductName") %></td><td><%#eval_r("UnitPrice") %></td><td><%#eval_r("UnitsInStock") %></td></tr></AlternatingItemTemplate>
        <ItemTemplate><tr><td><%#eval_r("ProductID") %></td><td><%#eval_r("ProductName") %></td><td><%#eval_r("UnitPrice") %></td><td><%#eval_r("UnitsInStock") %></td></tr></ItemTemplate>
        <FooterTemplate>
        </table>
        </FooterTemplate>
        </asp:Repeater>       
    </div>
    每页显示<asp:TextBox ID="txtPageSize" runat="server" Text="10"></asp:TextBox>条记录&nbsp;&nbsp;&nbsp;&nbsp;<input type="button" value="设置" onclick="return verify();" /><br /> 
    记录总数为:<asp:Label ID="lblCount" runat="server"></asp:Label>&nbsp;&nbsp;
    共分<asp:Label ID="lblPageCount" runat="server"></asp:Label>页&nbsp;&nbsp;
    当前为第<asp:Label ID="lblCurrentPage" runat="server"></asp:Label>页<br />   
    <asp:LinkButton ID="lbtnFirst" CssClass='n' OnClientClick="getHTML('f');return false;" Text="首页" runat="server"></asp:LinkButton>
    <asp:LinkButton ID="lbtnPrevious" CssClass='n' OnClientClick="getHTML('p');return false;" Text="上页" runat="server"></asp:LinkButton>
    <asp:LinkButton ID="lbtnNext" CssClass='n' OnClientClick="getHTML('n');return false;" Text="下页" runat="server"></asp:LinkButton>
    <asp:LinkButton ID="lbtnLast" CssClass='n' OnClientClick="getHTML('l');return false;" Text="末页" runat="server"></asp:LinkButton>
    </form>
</body>
</html>

.cs 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;
using System.Text;

public partial class RepeaterDemo : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            using (SqlConnection con=new SqlConnection("server=.;uid=sa;pwd=sa;database=Northwind"))
            {
                SqlDataAdapter sda = new SqlDataAdapter("select count(*) from products", con);
                DataSet ds = new DataSet();
                sda.Fill(ds, "productsCount");
                lblCount.Text = ds.Tables["productsCount"].Rows[0][0].ToString();
                sda = new SqlDataAdapter("select * from products", con);
                int count, pageCount, pageSize,currentPage;
                int.TryParse(txtPageSize.Text, out pageSize);
                pageSize = pageSize == 0 ? 10 : pageSize;
                int.TryParse(lblCount.Text, out count);
                pageCount = count % pageSize == 0 ? count / pageSize : count / pageSize + 1;
                lblPageCount.Text = pageCount.ToString();
                sda.Fill(ds, 0, pageSize, "products");
                lblCurrentPage.Text = "1";
                currentPage = 1;
                rp.DataSource = ds.Tables["products"].DefaultView;
                rp.DataBind();
                //lbtnFirst.Enabled = false;
                //lbtnPrevious.Enabled = false;
                StringBuilder sb = new StringBuilder();
                sb.Append("document.getElementByIdx_x_x('" + lbtnFirst.ClientID + "').disabled=true;");
                sb.Append("document.getElementByIdx_x_x('" + lbtnPrevious.ClientID + "').disabled=true;");                          if (pageCount == currentPage)
                {
                    //lbtnNext.Enabled = false;
                    //lbtnLast.Enabled = false;
                    sb.Append("document.getElementByIdx_x_x('" + lbtnNext.ClientID + "').disabled=true;");
                    sb.Append("document.getElementByIdx_x_x('" + lbtnLast.ClientID + "').disabled=true;");
                }//end if block
                ClientScript.RegisterStartupScript(GetType(), "disabled", "<script>" + sb.ToString() + "</script>");
            }//end using block
        }//end if block
    }//end Page_Load event
}

然后创建服务器端接收XMLHttpRequest 请求的文件,这里用的是WEB窗体,命名为 RepeaterDemoResult.aspx

.aspx 代码如下:

<%@ Page Language="C#" CodeFile="RepeaterDemoResult.aspx.cs" Inherits="RepeaterDemoResult" %>

<!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">
    <asp:Repeater ID="rp" runat="server">
        <HeaderTemplate>
            <table><tr><td>编号</td><td>名称</td><td>价格</td><td>库存</td></tr>
        </HeaderTemplate>
        <AlternatingItemTemplate>
            <tr><td><%#eval_r("ProductID") %></td><td><%#eval_r("ProductName") %></td><td><%#eval_r("UnitPrice") %></td><td><%#eval_r("UnitsInStock") %></td></tr>
        </AlternatingItemTemplate>
        <ItemTemplate>
            <tr><td><%#eval_r("ProductID") %></td><td><%#eval_r("ProductName") %></td><td><%#eval_r("UnitPrice") %></td><td><%#eval_r("UnitsInStock") %></td></tr>
        </ItemTemplate>
        <FooterTemplate>
            </table>
        </FooterTemplate>
    </asp:Repeater>
    </form>
</body>
</html>

.cs 代码如下:

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;
using System.IO;

public partial class ajax_xmlHttpRequest_RepeaterDemoResult : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        using (SqlConnection con = new SqlConnection("server=.;uid=sa;pwd=sa;database=Northwind"))
        {
            SqlDataAdapter sda = new SqlDataAdapter("select * from products", con);
            DataSet ds = new DataSet();
            int count, pageSize, currentPage;
            int.TryParse(Request.Form["pageSize"], out pageSize);
            pageSize = pageSize == 0 ? 10 : pageSize;
            int.TryParse(Request.Form["count"], out count);
            int.TryParse(Request.Form["pageNum"], out currentPage);
            int tempCount = count % pageSize == 0 ? count / pageSize : count / pageSize + 1;
            if (tempCount < currentPage)
            {
                currentPage = tempCount;
            }
            sda.Fill(ds, (currentPage - 1) * pageSize, pageSize, "products");
            rp.DataSource = ds.Tables["products"].DefaultView;
            rp.DataBind();
            Response.Clear();
            StringWriter sw = new StringWriter();
            HtmlTextWriter htw = new HtmlTextWriter(sw);
            rp.RenderControl(htw);
            Response.Write(sw.ToString());
            Response.End();
        }
    }
}

程序到这里已经完成了,可以运行看效果了。如果觉得样式简单,可以设置CSS来美观,这里主要是实现功能。


本文来自CSDN博客,转载请标明出处:http://blog.csdn.net/Sandy945/archive/2009/05/22/4208998.aspx

posted on 2010-08-31 11:32  幸福佑儿  阅读(399)  评论(0编辑  收藏  举报