代码改变世界

超大数据查询分页、

2010-09-10 15:58  北冥有魚,其名為坤、  阅读(793)  评论(3编辑  收藏  举报

大数据量的表用一般的分页会导致卡死,今天特意写了一个可供超大数据查询的分页。
页面代码如下:

代码
<form id="form1" runat="server">
    
<asp:ScriptManager ID="ScriptManager1" runat="server">
          
</asp:ScriptManager>
          
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
          
<ContentTemplate>

        
<asp:GridView ID="gvSysLog" runat="server" AutoGenerateColumns="False"  Width="100%"
         CssClass
="GridViewStyle">
            
<AlternatingRowStyle CssClass="AltRowStyle" />
                
<RowStyle CssClass="RowStyle" />
            
<Columns>
                
<asp:BoundField DataField="SystemID" HeaderText="系统ID"  Visible="false"/>
                
<asp:BoundField DataField="SystemName" HeaderText="系统名称" />
                
<asp:BoundField DataField="SystemIP" HeaderText="系统IP" />
                
<asp:BoundField DataField="UserID" HeaderText="用户ID" />
                
<asp:BoundField DataField="UserName" HeaderText="用户名" />
                
<asp:BoundField DataField="UserIP" HeaderText="用户IP" />
                
<asp:BoundField DataField="Category" HeaderText="分类" />
                
<asp:BoundField DataField="Message" HeaderText="具体描述" />
                
<asp:BoundField DataField="CreateTime" HeaderText="创建时间" />
            
</Columns>
            
</asp:GridView>
            
<div style="PADDING-TOP:10px; text-align:center"  >
                
&nbsp; 共<asp:label id="LPageCount" ForeColor="#ff0000" Runat="server"></asp:label>
                
<asp:label id="LTotalCount" ForeColor="#ff0000" Runat="server"></asp:label>条记录
                        
<asp:linkbutton id="Fistpage" Runat="server" CommandName="0" OnClick="Pager_Click">首頁</asp:linkbutton>
                        
<asp:linkbutton id="Prevpage" Runat="server" CommandName="prev" OnClick="Pager_Click">上一頁</asp:linkbutton>
                        
<asp:linkbutton id="Nextpage" Runat="server" CommandName="next" OnClick="Pager_Click">下一頁</asp:linkbutton>
                        
<asp:linkbutton id="Lastpage" Runat="server" CommandName="last" OnClick="Pager_Click">尾頁</asp:linkbutton>
                        
&nbsp;当前第<asp:label id="LCurrentPage" ForeColor="#ff0000" Runat="server"></asp:label>
               
&nbsp; 转到第
               
<asp:textbox id="gotoPage" Width="30px" Runat="server" AutoPostBack="True" MaxLength="5" ></asp:textbox>
              
<%-- <asp:Label style=" POSITION: absolute" id="msgbox" runat="server" ForeColor="Red" BorderColor="Red"></asp:Label>--%> 
               
<asp:Button ID="msgbox" runat="server"  Text="确定" CssClass="btn_2k3" 
                    onclick
="msgbox_Click"/>
               
</div>
            
</ContentTemplate>
            
</asp:UpdatePanel>
    
</form>

 

程序代码:

代码
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

using System.Text;

public partial class SYS_Manage_SysLog : System.Web.UI.Page
{
    
string strpage = "";
    
int PageCount = 0;
    
int RecCount = 0;
    
int CurrentPage = 0;
    
int Pages = 0
    
int JumpPage = 0;//跳到第几页
    
//每页显示记录数
    int PageSize =20//每页显示20条记录
    private static int PageIndex = 1;
    
private static int PageCounts = 1;
    
private static int JumpPages = 1;

    
protected void Page_Load(object sender, EventArgs e)
    {
        
if (!IsPostBack)
        {
            
//-------------------------------------------------------------
                RecCount = Calc();
                
//计算总记录数
                PageCount = RecCount / PageSize + OverPage();
                
//计算总页数
                PageCounts = RecCount / PageSize - ModPage();
                
if (!string.IsNullOrEmpty(strpage))
                {
                    
//设置当前页为返回页
                     PageIndex= int.Parse(strpage);
                }
                
else
                {
                     PageIndex
= 1;
                    
//设置当前页为11
                    
//Session["CurPage"] = 1;
                }
                JumpPages 
= PageCount;
                LPageCount.Text 
= PageCount.ToString();
                
//总页数
                LTotalCount.Text = RecCount.ToString();
                
//总记录数
                if (RecCount <= PageSize)
                {
                    gotoPage.Enabled 
= false;
                }
                
else
                {
                    gotoPage.Enabled 
= true;
                } 
            
//-------------------------------------------------------------
            GetMainData(); //绑定数据
        }
    }

    
#region "計算總行數"
        
public int OverPage()
        {
            
//算余
            int pages = 0;
            
if (RecCount % PageSize != 0) {
                pages 
= 1;
            }
            
else {
                pages 
= 0;
            }
            
return pages;
        }
        
public int ModPage()
        {
            
//算余
            int pages = 0;
            
if (RecCount % PageSize == 0 && RecCount != 0
            {
                pages 
= 1;
            }
            
else {
                pages 
= 0;
            }
            
return pages;
        }
        
public int Calc()
        {
            
//計算記錄總數
            DataSet ds= new DataSet();
            StringBuilder ass 
= new StringBuilder("Select count(Logid)  from DEG_SysLogs where 1=1 ");

            
string bss = ass.ToString();
            
int RecordCount = 0;
            ds 
= DEG.BLL.DbHelper.Query(bss);

            RecordCount 
= Int32.Parse(ds.Tables[0].Rows[0][0].ToString());
            
if (RecordCount < PageSize) 
            {
                Fistpage.Enabled 
= false;
                Prevpage.Enabled 
= false;
                Nextpage.Enabled 
= false;
                Lastpage.Enabled 
= false;
            }
            
else 
            {
                Fistpage.Enabled 
= true;
                Prevpage.Enabled 
= true;
                Nextpage.Enabled 
= true;
                Lastpage.Enabled 
= true;
            }
            
return RecordCount;
        }
    
#endregion


    
#region "翻頁"
    
public void Pager_Click(object sender, EventArgs e)
    {
        CurrentPage 
= (int)PageIndex;
        Pages 
= (int)PageCounts;
        
string arg = ((LinkButton)sender).CommandName.ToString();
        
switch (arg) {
            
case "next":
                
//下一页   如果要支持URL分页。 只要把CurrentPage 从URL获取就可以了
                if (CurrentPage < Pages + 1
                { CurrentPage 
= CurrentPage + 1; }
                
break
               
            
case "prev":
                
//上一页
                if (CurrentPage != 1)
                {  CurrentPage 
-= 1; }
                
break
               
            
case "last":
                
//最后一页
                CurrentPage = Pages + 1;
                
break
                
            
default:
                
//首页
                CurrentPage = 1;
                
break;

               
        }
        
//根据页数控制翻页按钮的可用与否
        if (CurrentPage > 1) {
            Fistpage.Enabled 
= true;
            Prevpage.Enabled 
= true;
        }
        
else {
            Fistpage.Enabled 
= false;
            Prevpage.Enabled 
= false;
        }
        
if (CurrentPage == Pages + 1
        {
            Nextpage.Enabled 
= false;
            Lastpage.Enabled 
= false;
        }
        
else {
            Nextpage.Enabled 
= true;
            Lastpage.Enabled 
= true;
        }
         PageIndex
= CurrentPage;
        
//获取改變后的页码
       
// //Session["CurPage"] = CurrentPage;
        
//用户返回到当前页
           
        GetMainData();
    }
    
#endregion

    
public void Alert(string rtt)
    {
        
//顯示提示信息
        System.Web.UI.ScriptManager.RegisterClientScriptBlock(UpdatePanel1, this.GetType(), "AjaxMsgBox""alert('" + rtt + "');"true);
    }


    
private void GetMainData()
    {  
        CurrentPage 
= (int)PageIndex;//获取当前页
        Pages = (int)PageCounts;//获取总页数
        LCurrentPage.Text = CurrentPage.ToString();
        
int PageSize2 = PageSize * (CurrentPage - 1)+1;


        
//用于函数参数的个数不对 在查询表达式 'isnull(max(xx.Logid),0)' 中。
        
// SELECT 子句中包含一个保留字、拼写错误或丢失的参数,或标点符号不正确。
        
//分页的核心语句,决定性能   row_number()也不错。也可以将以下语句改为存储过程。
        StringBuilder sql = new StringBuilder("select  top  " + PageSize + "  * from DEG_SysLogs a ");
        sql.Append(
" where   a.[Logid]>( select max(xx.[Logid])  from ( select  TOP " + PageSize2 + "  [Logid]  from DEG_SysLogs  where 1=1 ");
        sql.Append(
"   ORDER BY [Logid] )xx   ) ");
        sql.Append(
"   ORDER BY a.[Logid] ");
        gvSysLog.DataSource 
= DEG.BLL.DbHelper.Query(sql.ToString());
        gvSysLog.DataBind();
    }

    
//转到第几页
    protected void msgbox_Click(object sender, EventArgs e)
    {
        
string asd = this.gotoPage.Text.Trim().ToString();
        JumpPage 
= (int)JumpPages;
        
if (string.IsNullOrEmpty(asd))
        {
            Alert(
"out of page range");
            
return;
        }
        
if (Int32.Parse(gotoPage.Text) > JumpPage || Int32.Parse(gotoPage.Text) <= 0 || string.IsNullOrEmpty(asd))
        {
            Alert(
"out of page range");//页数超出范围
            return;
        }
        
else
        {
            
int InputPage = Int32.Parse(gotoPage.Text.ToString());
            PageIndex 
= InputPage;
            
////Session["CurPage"] = InputPage;
            GetMainData();//绑定数据集
        }
    }
}

 

效果图: